Everyone is different, but I usually get a headache when I'm herxing. I would still check with dr.
As Jackie says the headache might be the herx or like me, I was sensitive to the medications and had to talk to the Dr about the headache.
You don't always have to herx for the medication to work. Good luck!
The headache might BE your Herx, which is an increase in symptoms (not necessarily the same symptoms the infection was giving you) due to the die-off. Some symptoms can be a reaction to the medication too, depends on the meds and the patient. Everybody is different.
Why not call your doc's office and report what you posted here about the headache -- how bad, how long, what you've taken for it. Does your Lyme doc know about your previous meningitis? If not, tell him/her. If you told the doc already, still say 'My head is pounding worse than when I had meningitis X years ago', so that it's fresh in the doc's mind.
Lyme is a misery, that's for sure. You're not losing your mind, your body is just in a wrestling match with Lyme and whatever else you might have.
Three days would not, I don't think, be enough to make you feel better. It took me several months on med to feel better, and I didn't really get back to my old self for over a year. There was gradual improvement, so I was tired and worn out for quite a while. Your body has been through a lot to HAVE Lyme and then to GET RID of it, so have patience. Unfortunately it's not like getting antibiotics for an earache.
But do call your doc's office and report in anything that seems out of line, like your headache. There may have been some damage from the meningitis that is being irritated by the Lyme die-off, so a phone call to the doc to be sure it's okay to keep taking the meds would be reasonable.
Don't be afraid -- just be cautious, and know that there's still some distance you have to cover before you're truly well. Hang in there -- we've all been where you are, and we made it through too.