I just went through this myself...but my post-puncture headache started immediately after my spinal tap. It was crushing pain, and accompanied by projectile vomiting. Simply AWFUL. They first tried treatment with IV caffeine and painkillers; no improvement, so they did a blood patch. I felt good for a few hours afterwards, then the pain/vomiting returned. 4-5 days passed with continued agony and I was confined to lying on my back (could barely get up to even pee)...tons of painkillers, etc. but nothing helped. So I had to get a second blood patch. I went home and lay on my back afterwards for about 12 hours, didn't do anything strenuous whatsoever for the next couple of days, and was able to maintain.
I feel your pain on this one, I hope the blood patch works for you...it was the only thing that brought me relief, and it worked very quickly. Just make sure you don't "disturb" the clot that forms, so make sure you lie around for a day or two after it's done!