I agree with USUK. I already had two of them & they really are not that bad just alittle uncomfortable. Don't let people scare you!!
it is not that bad. you should be given doxycycline too, like the day before and 2 days after - in order to prevent infection. so with the doxy and the 3 advil, i would not want to take anything else. it is a weird/awkward procedure but it is not much worse than having a longer than usual exam/pap smear. you'll feel better if you are coherent and can understand what they are doing. they explain along the way and tell you what looks good/is normal as they go.
I would ask the doctor about it. When I had mine, I was told that Tylenol or another similar drug would be okay.