Guilt or cheating !?

So I have this boyfriend we been together for 3 years and just recently out the middle of where he will just start having weird ass attitudes and have a weird vibe as is I’m bothering him or something and honestly I wouldn’t do anything to him.. so I’ll ask him is he okay or what’s wrong and he will just be like nothing I’m like are you sure ? And he will be like “yup” in a sarcastic tone. So I’m like wtf ?? Then I’ll just give him his space for a little then he will hang up the phone and I’ll call back and I ask him why you hang up and his response is “I didn’t hang up” THEN WHO DID ??? How does a FaceTime call just hang up. Maybe he’s trying to start arguments with me just to get off the phone idk. Maybe he feels guilty about something he did. Maybe he’s just going through something HELP?!!