HELP!!! PREDNISONE PILLS MAKING ME LOOK REALLY FAT!!!

Hi all, I'm new to this site, but anyways, I have an immunity disorder in which its too strong and it attacks some organs, luckily its my eyes, it could've been something more serious like my heart kidneys or even brains. So sometimes it attacks my eyes and my doctor prescribes prednisone, I think I'm taking about 5 or 10 mg, I'm 13 by the way, and I think I've been taking it for a month, I stopped about 2 or 3 days ago, but it made me really fat, a lot of people have noticed I've gained weight, I've gained about 4 kg!!! (10 lbs) and lots have noticed my face has gone poofy all fat, and my belly got so bloated I can't wear anything anymore, I feel so fat, I've been trying to lose weight while on the medication but I didn't lose a gram, it was so hard to lose weight I just gave up, a lot of people are calling me fat now!! :( any techniques to lose the prednisone weight? Because I've never been fat all my life and now everyone thinks I just like to eat a lot, but since I stopped it 3 days ago, how much time does it take for my body to change back to normal? I really need some help people, and if you know some weight loss techniques ? Since I'm 13 it should be a little easy and faster for my body to change back to normal, so what do you think? I'm really worried.