Fluid sac on baby?

Today I went to my first appointment. The dr showed me what looks like a mass or fluid filled sac on it’s neck. She didn’t wanna say what it could be until the baby develops more & I go to a specialist. Im almost 9 weeks. I was wondering if y’all had something like this happen during yalls pregnancy & if it resolved itself. While google has lots of information its a lot of worse case scenarios. (This is the ultrasound the dr printed me before she found a better angle that showed it bigger & more clear.)