Will the way I hold my flute with my right hand effect my playing much?

Specifically, my right hand thumb. I don't hold my flute with my right hand in a C shape. My thumb slides to the side and the flute rests on the whole pad of my thumb, not just the tip of it. I'm pretty sure I'm holding it incorrectly, but when I hold my flute the correct way my pinkie finger locks (my pinkie is crooked and has been my whole life). Because of this I find it difficult to play faster notes when in the correct position. Is this something I could overcome or should I just keep playing my own way because that's what works best for me?