Complicated friendship

I am straight but i have been experiencing sexual attraction towards my friend he is also straight i just cant figure out why ,he is in a relationship and im also seeing someone ,we sit together in class we often play roughly but he mistakenly touched my private part it was painful so i did the same i touched him roughly is just that people were there it wss a bit embarrassing ,they was a tension for like 3 days after we got better and anytime when we playing our thing will get hard is just that we both hide it i only admitted to him that iam attouched to him only .can someone help coz i truly dont feelings yes i love him as my bro but i don't want to be experiencing this it never happened before or. Is because of my attachment? Coz i want him to date fameles the same way i do im okay with that is just that myb he knows how press me idk any advice coz i don't want it to be out of control.