Staying in

So my boyfriend is supposed to come over to hangout but my mom won’t be home because she works until 8. So we’ve been talking about hanging out a lot lately and usually my mom doesn’t let boys in my room but tomorrow I’m going to let him in since my mom isn’t going to be home. But I’m scared that something is going to happen and we’re going to end up having sex because we can’t keep our hands to ourselves when we’re alone but it’s usually in the den and nothing can happen with my mom in the next room but we’re going to be in my room today so something is bound to happen. What I’m scared is going to happen is my mom is going to come home early and catch us. She doesn’t usually come home early but I’m scared that tomorrow might be the day. What should I do?