Elavil (amitriptyline) for abdominal migraine, I was wondering if I am able to eat chocolate now, since it's a trigger. I ate chocolate the other day, no migraine.

Try it and see. Chocolate is a known trigger for some people's migraines along with other foods. If you can now eat it without causing a headache you may continue. I would be careful, however, and start with a small amount.
Not recommended. Elavil (amitriptyline) has been shown to reduce both the frequency and severity of migraine headaches. The chocolate is vasoactive substance and can trigger an attack.