Well, it took three months of trying, chickening
out, and trying again, but... I got it my cup in painlessly! At first I was so shocked at the fact that I couldn't feel the cup that I wanted to jump for joy, but I ran into a different issue... I could not for the life of me get the stem to stop protruding from my vagina. I tried pushing it up a few times, but it just seemed to slip right back down whenever I stood up. I eventually decided to leave it alone, figuring that if it didn't migrate on its own, I'd trim it later. The stem was rather uncomfortable, I wouldn't necessarily say painful, but it caused a slight burning sensation down there, and each time I bent over or sat down, I would feel a sensation similar to blood leaving my body when I'm wearing a pad... which was one of the last things I wanted to feel with it in. It kept making me think it was leaking, when it really wasn't. Next, my cramps suddenly got a lot worse, which I initially just attributed to me being anxious over using it for the first time. In addition, the cup kept making me feel as if I needed to poo... I'm not sure if I inserted it wrong or what, since I made sure to spin the cup and even wiggle it around for good measure before leaving it alone.
Eventually, after about 20 minutes, the discomfort became so much that I removed the cup... presenting yet another issue. Bearing down did. nothing to help the cup come down, and for a quick moment I panicked over the possibility of the thing suctioning to my cervix. However, I managed to get my middle finger up to the base of the cup to squish it in, but because I couldn't get the cup to move down with my middle finger alone, I used my thumb to grip the body of the cup and pull it down like that (I'm so glad I wasn't using a slick cup). Not a fun experience, but to my credit, removal was pretty clean considering the fact that I never touched the stem.
Shortly after removing the cup, the burning sensation disappeared, and I no longer had that awkward urge to poo. My cramps also returned to their normal level of annoying after a few minutes.
So my questions are, what exactly caused the bathroom urge? I suspected the cup might be too firm, but that didn't add up to me since I'm a fairly active teenager. In addition, would it be a good idea to invest in a slightly longer cup? I thought the long stem would be good enough, but apparently not since bearing down did nothing to help me, and I cannot imagine what I'd do if the thing were to migrate up to depths my thumb couldn't reach.