Can someone help me with boyfriend trouble?

I’m having problems with my boyfriend. He wasn’t responding all day and I finally got a message saying he’s ok. He said something happened earlier in the day but it’s fine now. He didn’t want to talk about it and said he would call me later. I’ve been trying to call him for five hours, and he either hasn’t picked up or has told me to call later or he’s busy. I’m feeling left in the dark and quite honestly angry at him. I don’t know if it’s fair for me to feel that way but maybe I’m just stressed. What is your opinion?