bad dreams

Oh my gosh, I think if I get another bad dream I will cry. Every night for the past 2 or 3 nights I wake up from having nightmares. I have gone so long without them like months, maybe years and now I keep getting them. I just want a peaceful nights sleep, dreams are okay just not nightmares. I honestly don't understand why I keep getting them. I didn't even watch anything on tv that would give me nightmares, except yesterday but it wasn't even scary what I watched.. it was NCIS (my favorite). I don't know what's going on.. it's just driving me crazy!