Hi Mommajoans, welcome to the board and congratulations on your pregnancy. Your doctor is really the best source of information. While some women may have some staining/spotting after sex, we can't know for sure what's going on and if you had anything more than just staining, I would suggest contacting your doctor. When you have any concern in your pregnancy, it's not necessary to wait until your next appointment to speak with your doctor, always call if something concerns you or you have a question. Your doctor knows the right questions to ask about how much blood, etc to determine whether you need to be examined further.
Good luck and I hope that everything goes smoothly.