Hello, I was just wondering whether "it" (whatever it is) could be due to an allergy?
Have you changed your eating-habits recently? Or has anything been changed with your equipment, living accommodation etc.?
With "things" like that we sometimes have to "comb" through everything on a daily basis to figure out the culprit and unfortunately it might take a bit of time...
Perhaps it also could be of help help to visit a doctor/medic/nurse with lots of experience who might be able to put you into the right direction to find out what it could be due to?
Good luck !!!!!