What's going on between us?

I don't know why lately but it seems like my husband and I are just not getting along at all. We fight over the stupidest things. He gets mad, I get mad. I get mad, he gets mad. Like tonight he brought up our trip to Las Vegas from a month ago. And I was listening to him and we were talking cool but at the end I said "I don't even wanna think about Las Vegas" but I really didnt mean anything bad. We both know our trip was not the best, not only did we both fight but we got into an argument with his friend who invited us in the first place. I didn't say it with it attitude, I didn't say it like I didn't want to talk because we had been talking. But he sarcastically said "ok nice talking to you" and I could tell in the tone of his voice that he got mad about me saying that? Like why? I didn't say anything wrong. We had been talking about the trip. And then I got mad and told him he takes everything offensive and he laughed and said it that I was dumb. So I said I would shut up and proceeded with what I was going to do anyway, take a shower. And he said ok goodnight AGAIN. Cause we've been arguing for the past few days. He's not cheating, at least I hope not. And I'm not cheating so Idk what's going on. But I'm getting tired of it and it feels like everything we go to sleep mad.