is it normal for a russian dwarf hamster to run in circles nearly all day? cause mine does that I dont know if it drinks or not but i know it eats. plz help!

it's been doing it the day after my first hamster died (it was really sick!) my first hamster bullied it but they were both brothers. The hamster i have now used to hide in the tube and sleep in the tube the other wud not let it out of it cause the hamster was terrified of it.
But as i said it's been doin it the day after my other hamster died. is there something wrong with it or is it normal?