Sex in early pregnancy (TMI warning)

I need advice and I can't see a doctor until I am 8 weeks and we aren't telling anyone until then, so I have no one to ask. My husband is well...endowed, and I'm on the more petite side. Sex sometimes hurt before I was pregnant, and now that I'm pregnant its even worse and I am so afraid we are going to hurt the pregnancy. Does anyone else have this issue? Should we just not? This is our first and it is so exciting, and I don't want to start it out by not having sex :-\