That happened to me. My dr told me to stop having sex for a week. Inside there are delicate blood vessels and depending on how you have sex, they can become irritated. Needless to say, it scared the b-Jesus out of me and I haven't been able to enjoy sex throughout my pregnancy since. It's been 8 months now. You will be fine - just take some time off and be a little cautious with sex. Good luck to you.