First Day of Workout

I am so damn discouraged. I have been doing this circuit workout and I have been working out pretty hard. And I am gaining weight. I put on some pants today that are always loose no matter how much weigh I gain and they were tight. I cant even believe that. I think if I wake up fat one more damn day Im going to scream. I can not do this anymore. I absolutely positively can not do this anymore. I am so serious. The only thing my ex's gf has on me is she is thinner. If I do not do anything else in this world I need to lose the weight and lose as much as possible,  I will move fat and I am going to get this weight off of me and I dont care what I have to do to get it off.