I've had headache since two weeks ago even after waking up i still have it when bending and sneezing worsens. what is the cause, should i visit a doc?

Multifactorial: Headaches can be tough to manage. If it's he worst headache of your life getting seen urgently is recommended. Persistent headaches can be associated with uncontrolled migraines or even rebound headaches associated with cessation of caffeine or even regular analgesic use (i.e Tylenol (acetaminophen) or Ibuprofen). Alternatively, a sinus infection could be brewing especially if you are feeling feverish.

New onset headache: Any Sudden onset headache should be checked out by a physician to rule out serious problems. I would recommend not waiting just call him or her and go in to check it out.