Hi,
How are you? It is good that the Ct scan and lumbar puncture were fine. If your headache happens whenever you have an activity, this could be due to exertion headaches which occur during or following physical exertion (running, jumping, or sexual intercourse) or passive exertion (sneezing, coughing, moving one's bowels, etc.). Majority of these are related to migraine and cluster headaches but it could also be due to organic diseases (aneurysms, tumors, or blood vessel malformation), which were ruled out. Try to avoid jarring exercises or activities that trigger these headaches. The headache tracker here in the forum may help. Take care and best regards.
By the way I don't usually suffer from headaches, this is a very recent occurence...