Yes. To be diagnosed bipolar you only need to experience ONE manic episode in your lifetime. For bipolar 1, it must last at least a week. For bipolar 2, it must last 4 days. Indeed, for bipolar type 1, the entire diagnosis is based on having mania. As long as you've had one episode, you're bipolar 1 (they don't even look at depression).

But I think your question is more along the lines of "I never have manic episodes anymore." I would say that's not that abnormal. The vast majority of bipolar folks spend most their time in either depression or normal moods. Mania is rare for most of us.

So really the key is to know whether you've had at least one true manic episode. Do you think you have at any time? (I am way behind in this thread, so I apologize if this has been answered).