depression
"I suffer from depression and has got to a very low point.  Doc prescribed me Sertraline.  First day, I didn't sleep.  Second day I had a tight chest and palpitations.  Third day, I had a fuzzy head.  Since then, it's been great.  I actually feel joy and am so much happier.  Give it a chance, I felt negative in the first three days but it takes time to work."