I dont want to seem insecure but could it be cheating plz help?

e? is he cheating? OK so on several different occasions my bf wont a phone and I could have just gotten off the phone try to call back an hr later or so and won't get an a next day it has happened three or. four times and fell asleep and I thinl to. myself how did. u fall as Today. we. talked all day and about 6:40pm was t talk. to him I tried calling him at 7:50pm and havent got a answer from him. since then I hjust sent him a lo saying I'm tired of him doing this and I'm done. b can't he stay by the phone I do the. same for him from him the. next day I. dont have a car to check go off his word. I know his ex still. calls him and a wanna seem insecure but I don't want to be a fool either any advice or am I overreacting