I think you're probably right. When I was really manic once, I decided I was rapid cycling. However, I tend to write off anything I decide when I am manic - I am definitely one of those "Maybe I'm not really bipolar! I just have complex PTSD!" when I am manic, etc. After posting, I read this:
3 Stories of Rapid Cycling | International Bipolar Foundation

And even the least rapid cycling of the three sounds like what I would call my "long" cycles and the shorter ones are what I was referring to more as moods. Maybe it's all just a continuum anyway.

I have plans to start CBT, which I hope will help.