Dear JA customer,
sorry to hear about your problem,
i am online today and will be happy to assist you .
diffuse body pains can be due to number of reasons, you have already undergone through routine tests ( almost all required as you say) , most likely cause is non-organic.
although it can be
thyroid homone problem, muscular problem. ( most likely you would have been tested for this by testing for tsh, and cpk level), viral infections including but not limited to hepatitis virus ( can sometime present like this)
it seems to be one of following reasons.
stress related. if you are excessively worried about anything or under a lot of stress, this can cause.
fibromyalgia ( especially if you have multiple tender / painful points on your body. this is a diagnosis of exclusion and respons to TCA s like amitryptyline.
chronic fatigue syndrome.
one very important thing you mentioned is that you are deficient in vitamin D. this vitamin deficiency can definitely and commonly cause symptoms you are experiencing. so you must replace vitamin D , and it can markedly improve condition.
what i recommend is following
replace your vitamin D.
do not hesitate to consult a psychiatrist because chronic pain often has underlying psychological cause. and relaxation techniques and therapies can work over sometime.
you can also consult a pain doctor.
and if it comes out to be fibromyalgia ( tender points with no other cause found), amytryptiline can help