Diagnosis' are quite generalized. You could be switching from those three diagnoses for ever. Focus on meds more if you are happy with what meds work then it's all good. You could think it would be better to know for sure that you have bipolar so you know that any time you could have some anxious mania any time but just using experience would be the same thing basically.

All those years of stimulant treatment could cause one to be more psychotic in the long term.

Ritalin (concerta) does make me have a very very mellow mood like an antipsychotic does. It's a common side effect.