How old are you luch? When I was 15 - 27 yrs, I had a very round, chubby face, rather resembling a football. It gave people the impression that I was fat, until they saw the rest of me and realised I was actually slim!
I am now 43 and my face is and has been a fantastic shape for many years. I have not aged like my counterparts and if I meet someone from years ago, they always remark on how amazing I look and how much weight I've lost! (Even though I'm pretty much the same weight) If you look at the singer Lu-Lu, she looks so much better today, than when she was younger, as her face was really round and chubby!
So you may hate it now (if you're young) but it will reard you 100 times as the years advance.
I hope this helps luchungkhanh!