I recently recovered from a seasonal fever, cough, cold etc which lasted two weeks. Of late I have been feeling really weak, get constant headaches and two days ago I fainted briefly while doing some stretching. I have lost stamina eg can't climb stairs like before. I also have a recurring pain going from head (throbbing pain) in a flow to my toes on the left side of my body usually. Menstrual cycle and digestive system is completely normal. Please suggest.