weird behavior from Dusty

[lovehamsters01]

Hi!
so Dusty is my Campbells hamster and has always been on the more interesting side. He has his quirks but until recently they were all within the realms of normal. He has a tooth that never gets worn down and I'm constantly trimming it, and he has difficulty chewing.
Recently, I noticed that he started making these weird squeaking sounds. I never heard him make any noise before and I've had him for 2 years already. (he's about 2 and a half). He doesn't act like he's in pain at all and is completely normal but he's squeaking for the first time ever.
He also went through a phase last Saturday where he was on his wheel for almost 12 hours straight until I finally distracted him with a treat, and he usually goes on his wheel for about 3 hours a night.
The strangest of them all, he's always been an extremely tame hamster who begged me to hold him although he could barely sit still for longer than a minute. Since Friday, he obsessively clamps onto my fingers and tries to pretty much eat them. It doesn't hurt because of his tooth issue, but it's super strange, especially as he's never bitten me before.
I know some of these are classic signs of pain but since his eating and drinking is normal, and his energy is through the roof, I was wondering if hamsters can get mentally ill as they age? He was literally clamping down on me so obsessively that the rest of him was practically dangling off my hand! this has been happening every time I take him out since Friday.
I am going out of town for about 3 weeks and leaving him with a friend and I plan to make him a vet appointment when I come back but I wanted to know if anyone can enlighten me on what's going on.
thank you!

[Miko]

The situation of your hammy is not that complicated but it can be if not taken to vet because the age is increasing and risks increase too. The teeth problems are very common ,you may not see it but he may be suffering from pain yk. Rapid increase in his activities is probably due to the pain I guess, as he may do such things to divert himself. I've experienced it that some hamsters just sleep all the time in pain but some become active. So we can't just judge acc to the behavior. I'd prefer to remove harsh objects from his cage and give him soft foods like homemade applesauce or mashed/boiled veggies. And if you're wondering that hamsters go mentally ill, They will be stressed due to health issues but mentally ill is not a case. Keep an eye on him and I hope he will be back to normal very soon.