Having bad dreams every night, and in a general bad mood, what to do?

Talk to professional. Occasional 'bad dream' r not unusual. Bad dream nightly, two weeks of 'moody', wonder if a true depression is present. Ur generalist (gp, general internist, family practitioner, nurse practioner, mphysician's assistant) would be the professional to start with. Dreams often are the mind's way of putting conscious experiences into an unconscious story. Jot them down, talk with a significant other...
Not enough info. These symptoms could be caused by multiple things. Have you recently started a medication? Have you been getting enough, uninterrupted sleep (7-8 hours)? Have you been eating properly? Have you had a major life event recently? Answering these questions will be a start to helping find a solution to your problem but if your problems are interfering with your life /decreasing function, visit a doctor.