pain after sex

my boyfriend and I used to have sex almost 3-5 times weekly. Well I went on a vacation and didn't see him for almost 2-3 weeks. when I got back we had sex, and it wasn't different from any other times we have had sex. but under the front of my hip bones I have thus tender/aching feeling. Does this mean there is anything wrong? or am I just feeling like this because we haven't done it know a while?