Kim,
When I read that sumatriptan didn't work, I was going to encourage you not to give up on triptans; like some other classes of meds, when one doesn't work often another will. (Sumatriptan didn't do a thing for my migraines either, but rizatriptan works every time as long as I don't wait too long.)
HOWEVER... when I got down to where you said you started on Cymbalta, my heart sank a little. Alas, it's not advisable to take triptans with antidepressants due to the possibility of serotonin syndrome.
triptans and antidepressants
An eye exam might not be a bad idea. As to what changed—spending more than usual time at the computer?
computer migraine?
computer headache?
Doc