<s>[INST] Hi my name is jim. A few days ago I got a really bad headache behind my eyes and then my nose started bleeding like crazy. The next night I woke up just soaked. I got really bad cold sweats. Since then I ve been getting headaches and the sweats. What could this be. [/INST] Hello Jim! Thank you for asking on Chat Doctor! I understand your concern and would like to explain that the most common cause of nose bleeding associated with headache is uncontrolled high blood pressure. Have you measured your blood pressure during this episode? The sweating may be related to an autonomic reaction to a high intensity headache. But I recommend consulting with your GP for a careful physical examination and some lab tests like : complete blood count, thyroid hormone levels, fasting glucose, kidney and liver function tests, coagulation tests and blood electrolytes to exclude possible causes of headache and nose bleeding. It is necessary to closely monitor your blood pressure during these days and especially during the episodes of headaches. A brain CT scan may be needed, if suspicions are raised for an intracranial cause of headaches (an infection, a brain tumor, etc.). Hope to have been of help! Best wishes,  </s>