Honey, it's normal to think like this, but no matter what you will always love your baby. When she's born & you get that first look at her & she looks at you, seeing her mommy for the first time, you'll feel that eternal love for her.
You know how many people get told that their baby will have complications, down syndrome, heart issues, mental retardation and then the baby is born & has none of those things?? MANY! If something is abnormal in a test or something, the doctor has to tell you all possibilities, without sugar coating anything. It doesn't necessarily mean that it's a definite.
You're only feeling this way now because it's your natural instinct to have doubts about your baby to begin with, and this on top of it is twisting that feeling around. It's normal. When you see your baby girl for the first time, that mommy feeling will come over you & you'll realize that it's not possible for you to NOT love her.
Relax. I'm sure everything will be okay.
My grandmother told me that when she was pregnant with my uncle, doctors told her he would be mentally retarded, and have health issues and that it's in her best interests to get an abortion. She said no (being the very religious person she is) she decided to keep him, no matter what risks. My uncle was born, healthy, no abnormalities, no health risks, and nothing is wrong. If she'd have listened to the doctor, she would be without him, we would have all been without him.