I had a spinal tap, after which I had severe headaches when I got home. The doctor told me it was a spinal headache, caused by cerebral-spinal fluid leaking out of the unhealed puncture point. It left the brain with insufficient cerebral fluid, causing swelling & headache.
He wanted to hospitalize me, during which they would give me a "blood patch." That's taking some of my own blood, and attempting to inject it back into the same place where the spinal tap had been done, to cause a clot.
I didn't want that. So we compromised, that I would remain flat on my back at home, no pillow, for at least 24 hours, with a minimal of movement. I had to drink lots of fluid to hydrate myself, and I was even given a bed pan and urinal bottle to use in bed (I only used the bottle). I was married at the time, so my wife brought me the water and watched after me.
If the puncture did not heal within 24 hours, and I still had the headache (which was blinding), I agreed to be hospitalized. Fortunately, it worked and I got better at home.
Ask your doctor if this is a spinal headache due to leakage of spinal fluid. It is potentially very serious, and you need to take immediately steps to deal with it.