Help. Morphology Scan Heart Issue

I had my morphology scan this afternoon. I'm 18w2d. Everything was perfect, and we found out we're having a baby girl 💗

But as we were finishing, the sonographer said she needed to go check with the doctor and would be back (never had this before) she came back in & said "now dont panic, but we couldn't find certain vessels in the baby's heart, we need u to come back tomorrow for another scan". She said a few other things along the lines of "it's just a box we need to tick off" I'm not sure cause my mind was racing by then...

I did see the heart and the 4 chambers, and the heart rate was fine. But thats all i know. I know she said not to panic, but what mother wouldn't?! Has anyone been in a similar situation? Any words to ease my mind? The next 14 hours are going to go slow 😭