Trisomy 13 NIPT Test

Tested positive for Trisomy 13 64% at 12 weeks. Went to a specialist and they said her brain was not fully developed at week 16 which was confirmed with babies that have trisomy 13 and don’t survive long after birth. They gave me several options including termination. Just odd to me because baby had been super active since the first ultrasound. I figured Id wait. I am waiting now week 21 to do another ultrasound in case things change. Has anyone else experienced this?