Die a virgin? lol
And if she has red hair, then its gonna look like her, genes for red hair are even stronger than genes for dark hair.
Anyway, you shouldnt be concerned what the baby looks like, I know its a cliche-but as long as its healthy-thats what counts.

Can i ask what age you are and what age she is? She seems quite immature.....which is worrying if she is going to bring up your child the majority of the time.

Then again, maybe having this child will make her grow up and stop being so selfish.
Are you sure she is pregnant and not just attention seeking?