Have Mental Health Questions? Ask a Psychiatrist Online
Yes it is possible that Bipolar Illness was miss-diagnosed. If the manic episode was substance induced then it could not count as the minimum 1 manic episode required for a diagnosis of Bipolar Illness. However, if you have a vulnerability to Depressive episodes and there is a risk of you experiencing a substance induced manic episode in reaction to anti-depressant medication (which it sounds like happened previously) then it would be common practice to treat the problem with an anti-depressant AND a mood stabilizer. In this scenario the mood stabilizer is used top prevent mania so that an anti-depressant can still be used. So, you may have been miss-diagnosed as Bipolar but you may still have been treated (or needed to be treated) in the same way.
I hope this has been of some help. Please let me know if you have further questions or would like me to clarify any part of my answer.