Hi, Welcome to Health care magic forum.
As you describe, the causes of unexplained weakness, in a 36 years old man may be the
anemia,
myalgia,
neuritis, or
tuberculosis.
I advise you to consult a physician for diagnosis and treatment.
I usually prescribe to my patient with such symptoms neurotropic injections for 10 consecutive days, and then periodically, vitamin D, and
calcium supplements. And pain killers when ever there is pain.
Avoid taking potato, other tubers, tomato, egg, chicken, and sea foods.
Take more of green leafy vegetables, pulses, sprouts, and protein rich foods to have good recovery, and resistance .
wishing for a quick and complete recovery. Thank you.