Am I weird because I don’t want to fool around or have sex with my boyfriend if my roommate is home?

We are all 24 years old and out of college. I didn’t go to college as a traditional student so I’m not used to hooking up if there is someone else home or in the dorm. I’ve also never had a roommate before until now.

I’ve been dating this guy for a month and he hangs out at my place a lot and if my roommate is not home we’ll fool around and have sex...but if she is home, I’m not comfortable with it. I don’t want her to hear us. Also, I wouldn’t want to hear her have sex with her boyfriend, so I find it as a common courtesy.

What do you guys think? Am I being a prude? How do I explain this to my boyfriend?