I've always felt pain, i have to clench my fists and breathe in and out, it's ridiculous. Then I volunteered to participate in a cervical cancer study, which involved speculum AND probe, every single month for 6 months. I noticed that some days I felt pain, others not. I think it depends on the doctor, the size of speculum, and your state of mind. I guess some days I was like "let's just get this over with" and my mind was on other things during the procedure, and other days, I was like "Oh God, another round of spec and probe, gulp".
Maybe if you tell the Dr that you find it very painful, they may know some techniques, or simply be more gentle. Best of Luck!!!!!