Round childlike face with a Bob?

Right now i am thinking of cutting my very long hair, and turning it into a shoulder lenght bob. I have a Round face with chubby cheeks, with side bangs right now. I was thinking a bob that was a little longer in the front then it was in the back. The longest part would probley be a little past my shoulder. So i was just wondering if that would make my face look fatter or chubbier. Also im kinda short at 5' feet, so would that make my face look fatter or more childlike? or are there other hairstyles that i should try or should i just keep my hair long, also its curly.