Hello dear, Thanks for being on healthcaremagic.com. If you would have presented to me as an outpatient,I would have given the following clinical explanation for your symptoms- Hemicranial headache(on one side of head) with retro-orbital(behind the eye) pain,when episodic,makes migraine as the most likely diagnosis as migraine is epidemiologically the most common headache disorder causing hemicranial headache but headache episodes waking you up from sleep are absolutely atypical for migraine.Here,it becomes mandatory to rule out any secondary cause of headache like a brain tumor or some other structural lesion.You should consult a physician and get a contrast Computerised tomographic(CT) scan of head done to rule out a secondary cause for the headache.I hope it helps.