Cymbalta is a VERY scary drug. I'm just now finding out how scary... honestly, I believe you're lucky to have had the reaction you did before ever getting it built up in your system.
I've been on it for 2 1/2 years (at least, maybe a little more but that overlaps my memory loss from shock treatment...), and for nothing. The whole time it was just because the original prescriber thought I should be on some anti-depressant, while it was Ritalin doing all the work. (Ritalin is my miracle drug, I would doubtless be dead by suicide if it hadn't been prescribed, and no, I'm not the least bit ADD.) I stuck with it thinking it was harmless, and since it was covered I didn't want to mess with my med combo. Now that it's not covered and is a major pain to obtain I've decided to ditch it. Now I find out it has horrible, sustained withdrawals - considered worse than those suffered from illegal substances by those who have experienced both. Even well-planned weanings can result in seizures, severe illness, loss of functions, and hospitalizations, with risk of death.

Anyway, now I'm irked and found your post while looking for information, and thought I'd reply since I'm sleepless from withdrawals and emphatically warn anyone reading to STAY AWAY FROM CYMBALTA!