I have been getting a bad headache for a week?

Anything. Your headaches could be coming from tension, dehydration, lack of sleep/poor sleep, skipping meals, stress, eye strain, teeth grinding, sleep apnea/snoring, or chronic sinus problems.
Bad Headaches. Did you take any over the counter pain killer like Motrin or tynlenol.Did it relieve the pain, are you able to sleep or pain keeps you up.Is your headache assciated with fever, allergy symptoms like sinus congestion.Have you had these kind of headaches in the past.Headach for a week needs to be evaluated by your physician who will ask you these question , find the cause and treat it appropriately.