.........think...please help....?

My fiancee has been acting very moody,snappy and grouchy lately.I don't know what's wrong.I know he has problems like school and gas but even with that he doesn't act like that.The last time that he acted like that was because there was something that he was hidding from me that I found out about later on (He uses o to masturbate and was thinking about breaking up with me but didn't).What do you think is wrong?I asked him and he said that he's just stressed about school and gas money.He's going to a university-FAU.I told him that we were on break until he would tell me what's wrong and he said"ok then I don't want to be on break so I guess that I'm just gonna have to make something up..your hair smells funny k?".Then later on he said he was just kidding.I don't know what's going on.Please help.