Thanks so much for all your support and advice.
Since my last post (I just asked which cup i should get,and you were very helpful) I bought a LilacCup, size small.
Once I got it, I decided to try a dry-run, and after struggling with folds and some lube, I got it in, but by then I had tried so many times, I was sore and it stung a bit, so I took it out..
Then I tried it yesterday when I got my period. I tried the origami-fold, but it didn't really work out for me, so I tried to punch-down fold, and it worked brilliantly! It was quite squished inside my vagina, but I was cramping, and I didn't feel like swoshing around inside of me, so I figured it would pop open by itself, but if it didn't, I was wearing a pad I had from my last period, anyway, so I figured this was just test-run.. I got it up quite nicely, and the stem was poking me slightly, so I thought that either it just had to pop open and 'migrate north,' or I'd have to trim it a bit..
anyway, I went to the kitchen to make myself some dinner, and after about 5 minutes, it popped open. I could hear it quite loudly, and man, it hurt! It felt like it had just pushed load of air straight into my cervix, it was so painful! So I thought "i have to get it out" and went to the toilet to get it out.. I panicked a bit, and considered just waiting, because I thought I might never get it out! But then I remembered what I had read, and relaxed, pulled down on the stem, squeezed the base and got it out..
So, I was wondering - have you felt that? is it normal to feel like you just had air pumped into your uterus and it hurt a lot? Is that what it's supposed to feel like when it pops open? I really want to do this, and do it right, but it was horrible =/