Saying that something is a headache ("These spreadsheets are such a headache!") has become synonymous with all kinds of annoyances, big and small. A literal headache, though, is more than an annoyance. There's no off-switch, no "close document," on a headache.
Coping with a headache involves first figuring out what kind of headache you have. Words like cluster and tension and ice-pick take on new importance when you're trying to understand the type of headache you have. If you do venture out to the pharmacy for some pain relief, check in with the pharmacist and ask a few questions. Some medications might be better for one type of headache than for another.