[Fluffagrams]

I've often thought for a young hamster to have to adjust to leaving their mother, then their siblings as well as having to adjust to leaving the relatively small enclosures of pet stores to be put into a larger cage on their own within a relatively short space of time can be pretty overwhelming and in your situation, I'd agree with Soufflé that a smaller and more basic set up could be beneficial.

I think that I might have seen the three tier cage that you have in a pet shop once and I agree, it's probably going to make taming more difficult. I would go with something like Soufflé has suggested - you can often find them at reasonable prices secondhand on eBay and the like and then you can upgrade at a later date. Even a Syrian at this young age is not likely to need a huge wheel and an 8" wheel is likely to be fine to start with unless your hamster is particularly large.