Well, those of you who suggested I try inserting the cup on my period were right, it was a lot easier, and I actually managed to get it in all the way this time, with a fold I couldn't use at all during attempted dry runs even (punchdown). I did it in the shower.

However, I kind of freaked out once I did. The stem was sticking out to one side for one. I managed to straighten it out, but I wasn't sure if it had created a seal at all. I tried feeling around the base but it hurt a bit, and that point I panicked and decided I needed to get it out, which was tricky, and uncomfortable (I pulled down on the stem until I could reach the base). Once I managed to get it out I heard this *pop* noise,so I was wondering if that meant I had a seal after all? There was already some blood in the cup but I wasn't sure how much of it was from my period and how much of it might've been from my struggle, like maybe I tore my hymen or something. In any case I've chosen against trying to reinsert the cup again tonight, though I intend to later during this cycle since I didn't have it in long enough to really see if I could feel it or if it would ride up or if I had any other problems.... I don't actually hurt down there as I type so now I'm guessing I didn't break my hymen as I thought I did.

EDIT: tried inserting it again today. I didn't panic as much as I did last time, but I was less successful. I tried walking around with it in and realized I could feel to to one side. It wasn't sore, but it was uncomfortable, and I felt some chafing. When I removed it I also realized it never popped open from a punchdown fold. I have a difficult time feeling for if it's popped open or not, since inserting my finger with the cup in kind of hurts, like it's way too tight. I almost certainly can't get myself to move my finger up alongside the cup. Anymore advice anyone can give me?