What did I do wrong

Just got off the phone with my friend (or whatever he is now) to see if he’s been doing better. He’s been going through a lot this past semester and when I checked up on him the weekend before our summer break started he told me he needed to be alone for a week. I understand that he needed his own time to himself and so I gave it to him. Just now I checked up on him again and asked if he was any better. He then told me he finds it stressful that people like me want to help him be less stressed when he just wanted to be alone. I told him I just wanted to help and that I was worried. He then stated that he likes being by himself with no one bothering him. I started crying cuz I felt he called me a bother. He then got annoyed that i was upset and that he doesn’t want to deal with me now and wants to be alone for good. I fear that I lost my best friend when all I did was try to help, this hurts me so much cuz I feel like I was nothing but a nuisance to him the whole time I knew him. What did I do to deserve this?