I would get a check up with a gp first and find out about your homone leves, etc. Then if they find nothing wrong there, I would get a psychatric eval. Good luck. Mood swings are no fun, I'm experienced.
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Bipolar I, Depression, GAD Meds: Zoloft, Zyprexa, Ritalin
"Each morning we are born again. What we do today is what matters most." -Buddha