Dear Amy,
Be patient with what is happening. My gut feeling is that you are fine. If you are seriously worried there might be some sort of anatomical problem, get a checkup with a doctor.
Your boyfriend is fine and this is not unfair to him. It is who you are and I suspect he is happy to have you. You are a couple and if he's a good boyfriend, he cares about your comfort and happiness. Try not to worry about this quite so much and enjoy the lovemaking for what it is. I suspect you two will figure this out before long. He will not be harmed by not being inside you a few days or weeks sooner.