I hurt my boyfriend really badly........???What should I do?

If he has his own place (apartment, condo, house, etc.) then you should go there and talk to him in person. He is probably not responding to your texts because he knows its from you. So i suggest you go to where he lives, and talk to him calmly and in a civil manner, perhaps over lunch or sitting in a chair in a garden. Go somewhere peaceful with him to talk, and remember not to yell; be calm.