I wouldn't worry about re-taking the DAT. Just research the schools you are applying to and make sure they don't have any automatic cut-offs for the DAT. I think Nova is pretty strict and will reject you automatically with a 15 on QR, but don't quote me on that. I would contact them now if you want to apply there, and you should get an answer from them within a few months.
With your GPA and DAT scores, I'd apply to at least 10-15 schools.