I have a headache thats started this past week. it lasts a few seconds but its so intense and comes every 5 minutes or so. any idea what's causing it?

Types of headaches: A number of things can cause ha one of which is stress-related. There are a number of ha: tension, cluster, migraines. If this is something new, its unlikely migraine but depending on location (one side or both, duration, other symptoms) its probably tension or cluster headache.

A form of migraine..: Any severe head pain that goes on for days can be considered under general category of migraine. Ths particular pattern may be a type known as cluster migraine. Regardless, new head pain that is severe going on for a week meds to be evaluated, would start w internist. There is a long list: sinusitis, reax to food/drink/sulfites, muscle tension, eye strain, brain tumors, cranial nn neuralgias, etc.