Get your doctor to do some work. You need to have a comprehensive list of blood tests to rule out everything it could be. A doctor would know. This will probably involve you having to starve for 12 hours and have quite a few tubes of blood taken, but at least they can rule out everything it isn’t. You should get your results within a week. Try and get your doctor to send you onto someone like a rheumatologist. Even they expect you to have had all the tests you should have had by now and just requesting a referral will put that preliminary task in place.
It could be a virus, it could a condition that require certain medication. You don’t know.
In the meantime, I would visit either an acpunture, oestopath, chiropractor or physiotherapist. Sometimes they can diagnose and help you deal with the pain. Because nobody knows what you have, it will be difficult for a while. Put the brain tumour idea out of your head because that’s way to worrying. I reckon you have something that you can get under control or that you may even be cured of eventually (Yipee!), trust me. Just get a diagnosis and then worry about what you have when you know. You can’t go through life in chronic pain when you have demanding little people relying on you.
Hope you get some solutions soon so you can begin to life your life and get whatever you have under control.
Don’t get me started on doctors. I have been misdiagnosed 7 times over the last 3 years. They make you feel like a liar and a charlaton but you have something genuine so keep turning up their until they get their fingers out. When I was eventually properly diagnosed by doctor said, ‘You didn’t say you had pain there.’ I said I did but you said that because I had such and such, I couldn’t have pain there. You KNOW what you have and where the pain is. Write a diary and go to the doctor with what you have to say written down. I usually hand it to the doctor because I get tongue tyed when I am with them. You have to give as much detail as possible.
When they diagnose you, read up and if you don’t think it agrees, go back and say so. At least you will get better medication whilst they figure it out.
Hope you get the right diagnosis the first time and get sorted real soon.
Best wishes.