What is going on with my hammie?

i once had the same problem before my hamster died. My hamster got really stressed from being in a cage which can be very small. So b/c of this my hamster stopped eating from all of the depression and i couldn't provide him w/ a big enough cage in time. I seriously suggest getting a bigger cage. They are all okay for a month or two but then they can get depressed as they grow. Good Luck.