Interesting..any chance she is eating too fast? She just sounds so damn healthy and that is a good history!!!! Often times they are strays found on the street but clearly not the case here.

Sometimes dog eat too fast as the feel competition and/or are just little piggies-the stomach says hey this is not even chewed and sends it back up. If this may be the case you could try feeding separately and small meals over the weekend-just trying to convey I don't think you have to run in for an emergency/after-hours appointment.

Millie so lucky to have you!
Take care,
B