Well its not senior year yet. If I were you, I'd do everything I could to raise that GPA. You have this summer, why not take a couple classes? Also, on aacomas, if you retake a class (at least a math or science), they'll replace the grade when figuring your GPA. Your MCAT score is going to be among the top end of DO applicants, I don't think you, by any means, NEED to take it over again. That energy may be better focused on getting A's in as many credit hours as you can. As others have said, apply early, and broadly- not just to the most selective DO schools (PCOM, CCOM, NYCOM, TCOM are some of the most selective ones).
Also, if you're thinking about dentistry, keep in mind that dental schools want one hell of a reason as to why an applicant is applying to both medical and dental school. I've been told by many a dental student that if you have in the past, or are currently applying to med school simultaneously, you're going to have a much harder time getting in.
Good luck.