I used to be athletic, always outside playing basketball for about 5-7 hours with out getting tired one bit. After a summer break with out playing/working out because of a looong vacation (3 Months..Added 15 pounds). When I came back to notice I was having very bad fatigue problems where I would get tired after 20minutes or so which I was surprised. During basketball my arms would get tired, and in practice I was having trouble doing drills/3 hr workouts which I used to do with ease. All of sudden I started getting back pains after standing up for long periods of time and pains in my knee, neck. I thought it might have been because of the long break so I started pushing my self to my regular routine but after doing so I would get dizzy,headaches, and fever like symptons after playing long periods of time. Does anyone know what may the be problem? or better yet how can I get rid of it?