Twin pregnancy

Hello 👋, I have been looking for answers with not much success. My AFP levels were extremely high at a 9.66 (twins should be about 4.8) .. I know their brains and spines are fine as I seen all of that at my high risk ultrasound at 13 weeks. However I am now reading there’s other things that could be wrong!! Has anyone had high levels (really high like mine) & their baby/babies were fine? I wasn’t worried at all at first but my Dr is acting like this is very bad 🤦🏾‍♀️