Our hamster was like this after we left him somewhere while we were on holiday. I think he had just adjusted to the new environment while we were away, and then went completely bonkers when we moved him home again. It was quite distressing as the constant running around was clearly a sign of stress. And we took him in his own cage and he was in the same cage the whole time.
Any change of environment will stress a hamster, so it's important to try and minimise this. Like keep them in their own cage if they go and stay somewhere else, and ideally keep them in the same home environment. It's better if you can have someone come in to your home to put out food and water, especially if it's only for a week-end or a few days. They can be fine without coming out of the cage for a few days, or even a week, if the cage is big enough, and this could be better as someone unfamiliar may not be able to handle them or there is a risk of escape.
It took Charlie about 2 weeks to stop being bonkers after we'd been on holiday and he didn't instantly go back to his old routines either. Clearly 2 weeks is long enough for them to forget a routine. Some routines he never did get back, but some weeks later he enjoyed his out of cage routines again mostly the same as before.
A point about ball running - hamsters shouldn't really be in a ball for more than 15 to 20 minutes - they can't tell you when they want to get out
. You can put them in again for another 15 to 20 minutes after they've been out of it for a bit though.
If you only got her in December she will have just started to get settled in and get some routines (it takes the first couple of weeks to settle in) and then it changed, and then changed back again, so she's probably a bit stressed. You can minimise the stress by having someone come round to feed her while you're away and by not doing frequent cage cleans. I've added Erin's Hamsters cage cleaning video below, it's full of really good tips that worked for me
The trick is to have a good depth of substrate - 6" ideally. Digging tunnels in deep substrate is supposed to reduce stress levels for hamsters. Also when the substrate is deeper, you don't waste so much of it. You just spot clean (ie take out the odd handful of wet substrate and replace it with another handful and mix it in so it still smells familiar) and do full cleans less often. Even then you only do 'partial' cleans, so not replace all of the substrate in one go and clean the toys at a different time/week.
As she has just had a change of environment recently, it would be best to go back to the thing that is important when you first get them, which is leave them to settle in for two weeks. So during that two weeks, don't do any cleaning other than spot cleaning (although it's alright to add extra substrate and mix it in, if the depth isn't very deep). Maybe only get her out if she is showing signs of wanting to come out and limit the amount of time in the ball. Sometimes they run a lot because they are stressed rather than for exercise.
Also it sounds like maybe she isn't tame for handling yet? Taming can take a few weeks sometimes, gradually. The dry bathtub is a good place for taming so they can run around safely and get used to your scent and being handled.
I'm sure she'll settle down again soon. You could also try scattering half of her food in her cage. Put one half in her bowl and scatter the other half so she can forage for it. They like finding food in the cage and foraging and this might distract her a bit and help calm her down. And talk gently to her through the cage so she gets familiar with your voice and scent again.
Cage size is important to their well being as well. Minimum Uk RSPCA recommended size is approx 80cm by 50cm of continuous floorspace. If the cage is a good size she will be fine being left in it for a few days.
My tip for cage cleaning is - use a potty litter tray - hamsters use them if you put it in the corner they have chosen as a wee corner. You can put Chinchilla bathing sand in the potty and the first time, put a tiny bit of wee'd on substrate on top so she knows it is still her potty corner! Our hamster uses his potty and the rest of the cage stays dry! I just clean out the potty about every 5 days or so.
My other tip is - their nest. You mentioned her being upset about you removing the nest. Their nest and hoard are their numero uno big thing in life! It's best to try and not disturb the nest if possible. Obviously if it has been pee'd in and is wet and stinky, you need to remove most of of, but try and leave a bit of the dry part behind so it still smells familiar and she can then rebuild it. Using a potty helps with keeping the nest dry too. Torn up white toilet paper is the safest nesting material. If you put a pile of this out she will pouch some and take it back to her nest to rebuild it. A pile in the corner is fine for her nest and means she can build a bigger one too. Most houses are a bit small for a good sized nest. Houses with solid floors aren't good either as they sweat and get smelly. It's better if they are open underneath and sat directly on the substrate.
If the nest is dry I just leave it and don't touch it
Also they get very stressed if their hoards are removed. They think a predator or some other animal has stolen their food and could start weeing on it to scent mark it. If the food hoard is dry, then leave it. If it has been wee'd on then it will need removing, but always put some new food back in the same place.
I'm sure soon she will get into a routine with you and things will calm down
But see if you can get someone to come round and just put some food and water out next time you are away for a week-end. That's all they need to do for 2 or 3 days. And best if they do it during the day while she is asleep so there is less chance of her getting out of the cage while they are doing it.
Anyway here's Erin's cage cleaning video and I added a little video I made on bathtub training - it's not the greatest quality but has a few tips.
https://www.youtube.com/watch?v=5jVnEjrXbww
https://www.youtube.com/watch?v=kjyEme2xcq4