Your resume is very impressive.
The one thing I'm curious about-- if you wrote your PS about your journey to lab animal medicine, have you worked directly with a DACLAM? That may be worth doing, to really prove you understand what a lab animal vet does. It's definitely different than the role of a researcher
As for your sanity check-- you are not uncompetitive! If you look through the successful applicants threads, you will find students with far less on their resumes than you who got in. I would hold out hope if I were you!