WHAT'S WRONG WITH MY FAT??

I am 19. This was for a wedding.

I have always had a bigger butt. I am 99 pounds and 5 foot, so pretty tiny.

It is bugging me because even though I like it, it make me have to get a bigger size in shorts and pants to accommodate it. People even ask me if I got butt implants. I'm in nursing school so obviously not.

Any ways to get rid of it fast? I work out and eat healthy already and am sick if it..