Ohkay, i need a moral help...?

i have become an addict...i had kept in mind to lose weight, winding up becoming 11 kgs underweight for my height, and became so by eating bare quantities of food and excercising like mad for 6 months...and now i am putting on weight cos i was almost dead by the end of the weight loss program which i did without proffesional consultation, and now i need to concentrate on my studies and i find that i am again becoming worried and 24x7 anxious abt the 11 kgs i have put on...feel guilty and depressed and stressed all the time, i even have sinus problem, head keeps aching, my bones ache, still i keep worrying abt losing weight...i maintain my excercises....i walk briskly for 1 and a half hrs daily incl. sundays, and still i am not able to lose weight, i consume 1000 - 1100 calories, but still...i just want to concentrate on my studies...my weight is 66 and my height is 5'8", and i am in the 12th grade, 16 yrs old....i want some remedy to divert my mind to other important things...please say something, that will boost up my concsience and that i really am able to concentrate on my studies...please help me...i am on the verge of tears and feel suicidal all the time...please help me.