My legs will shiver when I start feeling really good during sex. Or when I get kissed just right.
And when I'm up on top, as I get closer to an orgasm, my legs and hips will just shake uncontrollably and when I actually do come, I see swirling rainbows like oil on top of water and my whole body will shake even harder. Almost violently. I do retain a small amount of control, so I'm not going to hurt myself or my partner, but I can forget about standing up for awhile. And there's no way I could stop the shaking even if I wanted to. Immediately after this type of orgasm, I breathe in tiny, involuntary gasps like after you've been sobbing until I catch my breath somewhat and I still shiver for like 5 minutes.
I love having this kind of orgasm, but I don't know if it's really normal. The first time it happened, my boyfriend was a little scared and thought he might have to call 911. Does this happen to anyone else, and is there cause for concern?