Hello anmol! Welcome to HCM! Your complaints may be related to different disorders affecting the gastro-intestinal tract( black and grey stool, constipation), the musculo-skeletal system (fatigue, back pain, joints pain), the respiratory system (tonsils and cough) and general condition. These may be coincidental complaints or related to each other. The most probable cause in this case would be a metabolic disorder or autoimmune disorder. Anxiety and depression could cause a similar clinical scenario. I recommend consulting with your GP for a careful physical examination, a resting ECG, chest x ray and some blood lab tests as follows: - complete blood count - inflammation tests (fibrinogen, PCR, sedimentation) - fasting glucose - thyroid hormone levels and cortisol plasma levels - kidney and liver function tests - blood electrolytes - a stool analysis - anti streptolysin o titer ( indicative of post streptococcus infection complications). If all the above tests, result normal a psychiatric consult for depression and anxiety would be necessary. Hope to have been of help! Best regards, Dr. Iliri