I just did some weird vertical thumbspin that never caught and went all the way around my hand and back into the bottom of my palm. Is there something of this sorts already? I'll try to get it on video, and master it, but I was just wondering if it's a trick or not. (I'm very uneducated)

I'm not sure what you're doing from the description, but there is a trick generally known as palmaround, you most likely did a thumbspin to palmaround hybrid trick... Phya does a palmaround reverse in the evolution video

Did it go over the index finger?

edit: is it this? handaround.avi ( i slowed it down on purpose)

Yes similar, except I caught it in the same spot it started in.