As a reference, I usually wear size xs/s and I ordered the s. I'm also under 5'0 and the dress landed about two inches above my ankles.
The dress fit surprisingly very well, perfectly actually. I was worried the dress wouldn't fit but it's very accommodating and has a bit of stretch. The dress makes me look and feel very cute.
The material of the dress is pretty good. It's thick enough to not reveal anything underneath.
The strings that crosses the clavicles were a bit confusing since you have to tie it yourself. Once I got over that though, it was very cute.
I think the only downside is that there's always a very small gap whenever I zip up the dress.