Extremely upset at my boyfriend! How can i overcome this?

My boyfriend pissed me off so much, many times i havent heard from him in days, and he always has an excuse. First, it was because his phone cut off many times. Yesterday, he hasnt got back to me all day and then today when i heard from him, i felt so much anger inside of me n felt a need to express it finally, so i told him why didnt he get bak to me all yesterday? N he told me that he was high with his bruther and sorry. So i told him that im very upset with him and nothings gunna change that rite now bcuz he pissed me off. He doesnt understand how upset i feel because I really love him n we been datin since last year in august. Im still upset to this moment for an hour now. What should i do?