Please help, I need hope

Today I had my 20 week anatomy and gender scan. We found out that were pregnant with our first boy which we were so excited about, we heard his strong heartbeat and I left the scan feeling so happy and relieved. But later this evening I got a call from a Dr who told me that his brain doesn't look like it's developed properly. She explained that I need to travel to see a specialist for more scans and kept apologising because it didn't look good for my baby. She couldn't explain much more because she was very busy at the time. At this point I need advice, I don't know whether my son will be born handicapped or if he will survive. This is my 4th pregnancy and my 2nd baby, please if anyone has any advice or any experience with this please help me. Please pray for my son