Feeling like an imposter

Hello everyone. I'm looking for some advice, I think I've been misdiagnosed in the past. Long story short, in my late teens I've been in and out of mh facilities, and after years of treatment got the Bipolar 2 diagnosis when my gp suggested it because of my burnouts and depressions.

Back then I was desperate for a diagnosis because I was tired of not knowing what was going on in my head, so now in retrospect as a 31 y/o I feel like I've went along with a lot of the criterea of bp2 because I was genuinely convinced that 'this had to be it'. (Which im ashamed of).

At the time I really thought that I was BP. But now that i've done my treatments, been on meds for almost 10 years with no hypomanic episodes whatsoever (which i dont think I ever even had), and followed the signaling plan we've set up -- I noticed the complaints I have in fact do not get relieved with any of the tools and knowledge I have, and keep reoccuring. This was a huge red flag to me to look in.

I don't think I ever had any hypomanic episodes, just bouts of intense hyperfocus.
My exhaustion didn't just cycle with my depressions, I was and still am constantly paralyzingly exhausted, i cant power through a day without needing a nap. My intense reactions weren't because I was irritable because I was having a bad day, I was having huge meltdowns due to being overstimulated, overwhelmed and depleated. Socializing is difficult for me, it comes with a lot of rehearsing and it feeling unnatural, like I can't be spontaneous. And with these observations come a lot more that have me secondguessing my diagnosis, especially when I look back at me being a child.

As a kid, I had very specific interests I could deeply lose myself into. Example: as an 7 year old I had a deep fascination for poisonous frogs, had a whole bedroom dedicated to frogs (it was so green a neon green sharpy was nothing compared to it), knew everything about frogs, and even had a poisonous frog as a pet. Aside from that I remember having a hard time looking at people to the point where my mother had to constantly correct me, strong sensory issues and preferences with certain things, and a hard time fitting in socially with others generally.

I'm a very level-headed person and I look in a lot, and there's a lot of things I've glossed over in my life and especially childhood to fare along with everyone's drum. But I noticed that even with the tools that I'd been given I still do not feel better and 'functioning'. Far from the latter.

My gp brushed me off when I told him that I think I may be autistic instead, without even wanting to hear me out he brushed me off and shoved me back into that BP box. It hurt me and angered me to be brushed off like I'm an erratic person who doesn't know what they're feeling, like every thought and feeling I have is part of that BP rollercoaster I'm not even in.

Do you guys think it's right to assume I may be misdiagnosed and seek out help to look further into the possibility of being autistic instead? Asking, cus I feel like an impostor.