ok so you need about 2800 to 2850 calories per day. ON days you do football you need to increase that by 500 calories. So the days you do football you should be consuming at least 3,300 calories but i would do more like 3,500 calories just to play it safe because I am only guessing of how hard you are working out. That's a lot of calories and I bet you were not consuming enough. Have you been losing weight? IF so, then yes, you were not consuming enough calories. Now, make the calories count and chose whole fresh foods and not refined white flours, soda, candy, refined sugars, crap like that. THose calories are useless and will just make you get a temporary sugar rush followed by a very tired sluggish feeling and also belching/gas/bloat. Lots of vegetables, fruit, lean chicken, fish, lean pork, and fresh whole grains are what you need. Of course, you are young, so you can have sweets too, but just remember they are empty non-nutritious calories so the bulk of what you need should be coming from fresh whole foods. On a typical day of practice, from the time you wake up to when you go to bed, record what and when and how much you eat, drink and what the food item is and how much of it it is. I can tell you if you are getting enough or not.