I had daily migraines for over 6 months that finally went away 2 months ago with high dose 5htp (now 500 mg) a day. since thursday i've had another migraine that won't go. what can i do?

Migraines: what medications have you been on before? Have you had a ct or mri of the brain? Taking vitamin b6 and excedrin migraine may help. There are multiple prescription medications to try. Preventative medicine is an option too. See a doctor or neurologist for this

See your doctor: Your past history suggests chronic migraine (although part of the history is missing - duration of headache) which implies the need for prophylactic therapy. Since you have been prescribed medication by a doctor, it only makes sense to go back to that physician to address these episodic migraines and therapy, particularly as breakthrough headaches. See your physician for further discussion.