Weight Gain

I'm not really sure when it started but I've recently have gained almost about 15 pounds and quick. I'm 5'7 so you cant really tell but I feel it and see it. I'm getting to the point where I'm getting discouraged on to even go out or take pictures since I feel like my double chin shows. Today I tried one of my fav. jeans and it TIGHT now. Like ik I need to change my food choices and workout atleast a bit but i think about it and my mind just wants to eat more. I feel like everyday I need to eat a sweet . Like today for ex for lunch. I ate mcd. I ate 2 burritos, 1 hashbrown , 1 spicy chicken sandwich and a medium frappe. Also, i ate about 4 small size Hersheys. I need some tips on how to get rid of this sweet tooth also, and maybe some tips on weight lose.