Am I being too sensitive about my mom’s comment?

I’m 18 years old and I’m about to leave for college. So earlier this summer I told my mom I had sex and I wanted to get birth control. We went to the docs and got some. However, she was upset and keep telling me she was “disappointed in me” but I thought we have moved past it. However she told me today that because I have birth control “doesn’t mean I have the white flag to go hog wild” at college. And she said don’t be a hoe like so-so. I kinda laughed it off and I’ve been trying to forget it but I can’t. It really hurt but my mom has said I’ve been “too sensitive” about things she has said I’m the pass. So am I overreacting to her comment or am I right to be upset?