Its very different for everyone... i've had this procedure a few times as it took years for us to get pregnant.
The first time i was under general anesthesia for another reason and my doctors coordinated it so that i could be out for it.
The second time it was HORRIBLY painful... that being said, i have many issues in that area -- had aggressive cervical cancer and the surgeries for that led to horrible scar tissue that narrowed my cervical canal (so i'm sure that didn't help)... plus my tubes were blocked and with the dye they inject, they try to push the blockage out, so i hear that makes it hurt more... the basic pain meds they suggested definitely didn't help me! You may be one of those people who have no problem with it, but just incase i'd recommend taking the vicoden!
I think it has more to do with your anatomy than your pain tolerance because i have a very good pain tolerance with other procedures i've had, but for me this one was bad.
on average though i've heard most people just have bad cramping.
as far as how long it takes... it was fast, maybe 10-15 minutes or so...
and as far as fertility, i've heard it increases your fertility for the first few months because it clears and lubricates your tubes!
Good luck!!