Discomfort

Alright I'm going to try to explain this the best that I can. So when I'm having sex with a guy and they know that I squirt, they finger me intensely to make it happen. Usally in the beginning it's fine and all, but then after a while it starts to feel physcially uncomfortable...it's like after enough times I just want to say "Okay stop stop, I'm good." Which I eventually do say that, but it also feels weird because I don't wanna be done, but I am because of the discomfort.

My question is...is this normal and can anyone possibly help me know why that happens? Thank you!