If you want to keep hairstyle and good look with oversized sunglasses, You shall makeup proper hairstyle. For example, wearing oversized sunglasses, you shall leave too much bangs especially straight hair bang in your forehead. If you like bangs, you can leave some on each side of your forehead. If you just tied your hair up and not leave bang, I think the sunglasses won't mess up your hairstyle.
Yes. Sunglasses can easily mess up the hair especially when you put sunglasses on your head. To prevent the sunglasses from ruining your hairstyle, you'd better replace the mousse with a root-lifting spray. And you can pull your hair back with hairpin secured firmly. Or you can just wear braids which won't be ruined by your sunglasses because it can stay in place for a long time. Hope this helps you.