Hi Hope,
My fiancé takes it; he's an alcoholic and been in recovery nearly six months.
He's suffered from depression and PTSD for some years, he started taking 5-HTP soon after coming out of the detox clinic and it seems to be working well for him.
He has had no side effects from it, maybe you started on too high a dose for you.
Try starting with lower doses and work up to the correct one, it's also recommended that you take it at night as it helps you get a better quality of sleep.