At my 20 week scan (I am 27 weeks now) I was told that my baby had Talipes of the right foot and had some minor concerns regarding her heart - at the time I was really upset, I was all prepared to go for a scan, find out the gender then be sent on my way.
It's my nature to ask a lot of questions though, and I think I managed to get myself in even more of a state because every worse case scenario was playing out in my head - as midwife said thet Talipes and heart issues are soft markers for Down Syndrome. So perhaps the sonographer did you a favour by giving you space to digest this new information ahead of your fetal medicine appointment.
I would try and write down all the questions / worries you have before you go because in the moment you may forget to ask them when a simple answer from the doctor could have crossed them from your list.
What also helped for me is I talked to my husband about what we would do if it WAS worse case scenario - so I felt prepared for bad news as well as good - and knew we were on the same page about everything. It is a hard conversation to have and think about, but I found everyone elses "I'm sure it will be okay" approach annoying (though I understood they were well meaning and hoping for the best), as it might not be, and I wanted to be prepared for that too.
A lot of people advised us against googling and research ahead of finding out the exact situation, and they were probably right, but we still looked anyway. I am sure all the doctors and specialists are used to this now and our doctor had to put a few of my concerns that I picked up from this activity into context for me, but I was still glad I mentioned them as they were put to rest.
Hope you get good news at your next scan x