It's normal, hamsters usually fluctuate in weight. The mix you are feeding her is likely different to previous too so it's probably helping her gain weight. Hamsters are very good at monitoring their weight and don't over-eat, though do put on weight if they don't get any activity so as long as she has a wheel and time out of the cage she isn't 'obese'
The white tooth may indicate a problem though I don't know much about hamster teeth as never had a problem with any of mine. It's normal for them to be a darker colour, but maybe ask about the white one when you go to a vet next as that could be the issue.
Your robo seems fine as well.