Adam brings up a good point. Vaginismus is an unwanted, rather...forceful...tightening of the vaginal walls that can make sex painful or impossible, depending on severity. Not saying that's necessarily the case, but it's a possibility. Why not bring up the issue next time you see your doctor?

Anyway, for now, my advice is making sure you're ready, so to speak...if he's not getting you adequately aroused, you're not going to be physically ready for anything, and it's not going to be comfortable. Foreplay is a hugely important step in the overall process.

Do take care, and I hope things improve for you.

Hugs,
Harley