Emotional beyond belief pleas help!

I have had these horrible outbursts of emotions lately. At least one per week for the last month. I cry my eyes out and cannot stop for a couple hours. I honestly cannot tell what this could be from. I have a stressful job but I still love it (I'm a nurse) I am in a LDR, and I'm in school. These "breakdowns" are extremely hard on me, and frankly getting really annoying. I'm a very strong person usually. Is this normal?! Should I consult a doctor? I use to be on depression meds, but that was over a year ago. I need some real advice, or maybe just some words of encouragement.