I wish had the answer tank, are you recently diagnosed? I've had fibromyalgia for years, pain of some kind everyday with massive flare ups every couple of weeks or so and all I've learned is how to manage it by not overdoing things and pacing myself. I don't take heavy duty pain relief as it just causes other problems but I was prescribed a low dose of atenolol for the the constant headaches I was having and it's been very successful (up to now). Know your limits, if you're having a bad day be kind to yourself and learn to say 'no, sorry, I can't do that today'...try to keep your mind occupied, even if you have 'brain fog', and there's nothing like a good laugh to make you feel better. The hardest part is getting other people to understand. Look for FM forums online, some of them are very helpful.
Good luck.
Kathyan you're lucky that amitriptyline works for you, my doctor's mentioned it to me but I'm a bit reluctant as some people have bad side effects.