EDIT: Got it in today (the first day of my period) :D Thanks for all the advice everyone!
The real problem here was I didn't like the idea of tampons, AT ALL. The whole shoving a piece of bleached 'cotton' up there didn't sit well with me. It seemed like a breeding ground for bad things, and the raised risk of TSS thing scared me. I've used pads forever, and I hate them since I always leak (I have a fairly heavy flow) and the smell, and sitting in your own blood didn't make me a fan.
So I found cups! I was really excited, since it seemed they had the advantages of a large tampon's capacity, without the bigger risk of TSS. And I could move with it in. Plus, the potential to get rid of cramps appealed, since I've had them so bad I've ended up in the ER and vomiting when I try to get up (or move or breathe). Mom wasn't too sold on the idea, since she didn't think it was very hygienic, to which I rolled my eyes because like pads and tampons are? And it's my body, and the idea didn't bother me at all. So, after some research on here, I went with my gut feeling, and got a small Lunette Selene. It came in the mail today and I was so excited, since my period is due either tomorrow, or Monday. Just in time.
I decided to take it for a spin. Two sessions, and a painful and sore bottom later, I'm somewhat at a loss. I've read through practically the whole insertion tag for painful problems, tried different folds, lube, took breaks, relaxed, used different positions, everything. I got it the most far in using the punchdown fold, which I like a lot, but I still couldn't get it all the way in due to the pain. Any advice would be helpful. Because I really want to use the darn thing, but it's frustrating when it's just pain for me, and others seem to slip it in no problem. Should I wait until I actually get my period to try it? I didn't think it would matter much, since it's so close anyway.