Woah is this big! I’m 5’6” about 140lbs-150lbs and I got a medium in this dress. Ally did say it ran big but I still went with the medium because I’m tall and was worried it would be too short if I went with the small. Definitely wish I had went with the small now because it’s soooo big in the back (the stretchy part). It’s more like a large or extra large. I love the dress and I’m going to keep it but I’ll have to fix the back of it. It’s really just that stretchy part that’s too big and causing an issue. Thankfully it’s an easy fix.