We broke up now I’m scared

I broke up with my bf today and honestly I feel bad I don’t regret it but just lost interest right. But I got to the point where he said he wanted to be left alone so u blocked him and now I’m so worried he’s going to self harm and one of the main reasons we broke up is I devolved feeling for a good friend of his but that friend that I like had a gf. And it didn’t help that he stayed with me all night and dealt with my bs all night which is something no one has done. I’m so confused and scared. This is more of a rant sorry.