Sex with best Freind

My bestfreind and I had unaprotected Sex last night and before we did it he told me he loved me ...what do I do. In the past he said he wants me to be his girlfriend and have his kids but we argue a lot so idk what to do we argue and make up 
I DO LOVE HIM TOO! 
We just get mad at each other over stupid little stuff like he gets mad if someone text me