I'm pretty certain I don't have ASD, but I also tend towards obsessions about things.
They usually start with a famous person that attracts my attention for any number of reasons, then diverts to an assortment of related pieces of work they've done, or someone they work with, and then it usually settles on something that lingers for a LONG time.
My most recent "big" obsession was the musical 'Spring Awakening'. But I can trace it right back to one man I saw in a random YouTube video, singing a song from a completely different show. And through a really complicated twisted path of interests, I got to the musical.
The obsession was STRONG through most of 2019, then started to drift off. But the stuff I'm moderately interested in at the moment can still be traced back to that ONE YouTube video. My brain has yet to find it's BIG obsession for now. It's in its "toying with different things" phase.
TBH OP, I'm fine with it. It's just the way my brain works, and when I think back, I realise I've been like this for YEARS. It's never caused me any problems, or caused any hurt.
What about if you stopped being embarrassed, and just rolled with the obsession and let it naturally play out. You're not hurting anyone, and if you enjoy it, what's the fuss?
I've had some of the best experiences of my life, as a direct response to my obsessions, so why not enjoy them?