You need to go to the police and report the incident immediately. Don't worry about your mom upset. Don't put up with this. If you put up, then this ass will continue to abuse you.
If he rape you again, go straight to the hospital and tell them so they could collect his DNA as evidence. Otherwise, he could deny it.
It broke my heart to read your story.
I am a single mom with a 10 year old girl. I reminded her everyday that nobody can touch or see her private part. Even I can't see her private part.
I tell her to report to police if anyone hurt her and touch her inappropriately. I also told her to tell me everything, and not be afraid.
With that being said, you must report this incident to the police so this ass guy can go to jail, so he can't hurt you or other kids. They will register him as sex offender FOR LIFE!
Good luck and be brave. You can do it!