Another yay for lamotrigine! (I don't own stock in any pharmaceutical company, just so you know. )

Callmeruby, Ruby, I think having side-effects of meds are in no way indicative of the validity of any diagnoses. It sounds a bit like you feel that way.

I agree with most/all posters that you should find someone to figure out what's exactly wrong, without blinding yourself in your search by categorical labels for syndromes.

If the belief you have BP (or any other belief) used to be extremely, pathologically, strong, it might indicate some psychotic tendencies, but there are quite a few psychotic disorders. It doesn't really matter which. It could however mean that some of your meds are working, because you started doubting your diagnosis.

Doubt is a sign of mental health (unless it comes out the other end and becomes neuroticism, but even that can be preferable because you see the problem and you can fight it).