When you were born the bones of your skull were soft so your head could pass through your mothers birth channel. Then the separate plates of your shull knit together and harden. Durring this time the skull can have its shape flattened by laying in your cot for long periods without moving. It eventually hardens in this shape. To reshape, the skull can't be reshaped. Perhaps collegen can be injected under the skin to puff out areas. Or more drastically, the skin peeled back and an implant fitted, like they use for chin implants. You could make an appointment to see a cosmetic surgeon for advice.