Ooh the photos are a bit small! I would ignore the 280 pixel height, and just shrink your original photos about a quarter of the file size they are now. If they're less than 120kb in file size they should upload fine
I can't see a lot from the photos I'm afraid.
Ooh - I just clicked on them and they went a bit bigger so got a good look. Your hammy looks asleep in the corner. Is he like that a lot? Out in the open I mean? Rather than asleep in a house.
The cage does look very small so not a lot for him to do in there. I think the main thing at the moment is to have a health check done by a vet as I noticed you mention scratching a lot elsewhere. Although as Shannon says, they can do that a lot normally anyway as they're always grooming. I wouldn't worry about it unless he scratches so much he creates sores.
Looking at the cage picture again, there are a few things you could do to make his life more hamstery and give him some enrichment, which might help him perk up a bit.
The substrate seems to be a cat pellet type which will be quite hard, and it isn't very deep so he can't do any digging or burying things. They actually like to dig tunnels if it's deep enough!
You would be better getting a paper based substrate that is softer and you can have it a bit deeper. I think that would make him happy. Kaytee Clean and Cosy is a popular one. Carefresh might be easier to get hold of locally. Whichever it is, make sure it's not a scented verysion. Longer term you can buy Fitch in bulk which works out cheaper, if you can buy online.
Also a few more hidey places in there would probably make him happy. I can see a little ceramic house, but that won't give a lot of room for moving about,
You can make an additional house out of a cardboard box - eg a tissue box - which would be slightly bigger and allow him to have a cosy nest and bury his hoards under his nest. So you'd cut the base out of the box and a hole in one side for a door and sit the open base on top of the softer, deeper substrate, so he can burrow down inside.
To be honest I don't think he'll be very happy with the current set up as he doesn't have a lot of room to run around or places to go. And he won't be able to have normal hamstery behaviours.
For now you could just tear up a load of plain white toilet paper into strips and put plenty of that on top of the current substrate - it'll be nicer for him and he may pouch some to build a nest.
I guess with a little cage like that, and not much substrate, you've been needing to clean him out a lot and so he'll be even more unhappy about that. Because it removes all their familiar scent.
They need to be allowed to have a hoard. So if the hoard has to be removed, then replace it with new food, where you found the hoard. It is difficult for them to have a hoard if the substrate isn't deep enough.
Cage: He really needs a bigger cage. It doesn't have to be enormous or cost a lot.
Something like the Alaska cage on Zooplus is a good size and comes with a platform and a ladder as well. It has a good deep base for lots of substrate. Basically the more substrate you put in, in a larger cage, the less you use in the long run because you can spot clean mainly.
https://www.zooplus.co.uk/shop/small...r_cages/284288
This one is also a good option, but it costs a bit more and only has top opening. Whereas the Alaska has a nice big front door which makes it easier for interacting.
https://www.amazon.co.uk/Little-Frie...gateway&sr=8-1
Or a cheap option, if you don't mind a bit of diy - is to make a bin cage out of a plastic storage bin. The Ikea Samla 78cm bin is cheap and is a good size. It means cutting holes out of the side panels and lid and attaching mesh for ventilation. Although to be honest, by the time you've bought all the bits and pieces to do the job, the Alaska cage can work out as cheap.
https://www.ikea.com/gb/en/products/...-art-90102971/
Here are some examples of bin cages
https://www.google.co.uk/search?q=ha...w=1252&bih=554
If you have a Pets at home nearby, they make a cage that is a good size for a dwarf hamster - not too big, not too small. But it costs more money than the Alaska cage (which has free delivery). It's described as extra larger, but isn't big enough for a Syrian hamster (and it is sold for that purpose). It's a good size for a dwarf hamster.
It also comes with a shelf and a ladder and has a good deep base to fill with substrate. The little plastic house is pretty useless though.
https://www.petsathome.com/shop/en/p...me-extra-large
Just to let you know I have had exactly the same thing, with our last hamster. I got a cage that seemed ok but was far too small. Our hamster got lethargic and depressed and then aggressive and a kind of cage rage. I googled a bit and found this forum and got him an 80cm x 50cm cage (he was a Syrian). You wouldn't believe the change in his behaviour - he had a great time in that cage and was almost smiling.
With a bit more space in the cage you can add a lot of "enrichment" to keep them stimulated. Lots of cardboard tubes for tunnels and little hidey places. A shelf or platform is important too - it's somewhere to go that they can sit on, and they can also sit under it to feel secure.
By the way your hamster won't have wet tail. It is why I thought you had a Syrian hamster, because only Syrians get wet tail.
This is another cage that is popular for dwarf hamsters. It's a perspex tank style. Again not too big, not too small. And a good deep base for substrate. There isn't a shelf in it though so some kind of platform could be made or a large house used as a platform.
https://www.portonaquapet.co.uk/shop...a-Multy-M36261
It makes sense really. They don't have much of a life in a very small cage and can just sit, eat and sleep. With more space they can go places and do things, and dig tunnels and have favourite places to sit.