hello madam.. symptoms:headache joint pains weight gain and cramps.. i want some more details like your age smoking drinking or other addiction history..any previous or recent illness.. what all blood tests were done?your hemoglobin and protein levels?blood sugars? it would be helpful for me if you can upload all the reports.. head ache at what time of day, duration ?hows your vision? SORRY FOR PUTTING SO MANY QUESTIONS.. with loss of appetite i think you are in malnourished and deficient of protein vitamins.. yes with malnourishment you gain weight.. is your thyroid profile done..that could be the most probable cause.. something jumping inside body!! i would need above details to solve the problem..and actually it can be solved..donot worry.. if you have something bothering mentally dont hesitate to meet a psychologist/psychiatrist.. until then start taking vitamin supplements and a balanced diet (with sufficient protein) we will go further with your reports.. hope my answer helps you if you have any more queries i would be happy to answer..