Which disease i may have with the below symtoms?

Im 30. Since the last 6 months i feel i'm reducing my weight like anything. Even though i eat properly ( the normal way i used to eat), i am not becoming fat, rather becoming thin day by day. the way my hands, my arms, my kegs , my butts used to be, it has reduced a lot. it has happened such that i can not put even my old clothes.( they are becoming loose for me). I smoke around 15-20 cigarettes per day and booze twice a week. Even i have problems with sex also. i dont get aroused easily and if i get it , it stays just for a min or less. i was checking with the ill effects of smoking, but no where it says about the weight/ body loss. even i was looking for the aids symtomps, but i dont have any other except for weight loss. I had a blood test some 2 months before , but i'm not sure if the blood test came true( which says i'm not HIV affected). Please help as im getting into one more symtom of AIDS that is depression because of this weight loss.