my clit is ticklish?

I really enjoy being eaten out and fingered, it all feels good, but why is it that everytime the man starts to focus on my clit it feels crazy ticklish? to the point I can't even keep still and instinctively pull away!? Also, I've had oral, anal, and vaginal sex, all many times, and I still have yet to cum OR orgasm. I'm just very confused, and honestly pretty frustrated with my body right now.