Could I Have A Mood Disorder?

Or could it be just part of my anxiety? Lately my moods change pretty quick. I can be really happy and optimistic in the morning and then in the afternoon I can be depressed and pessimistic. Sometimes it changes quicker than others and my moods can go from happy to sad to angry to annoyed. I know it wouldn't be bipolar but does it sound like a thing that's separate from my anxiety or connected? If you need more info ask and I'll post it