I am going to shoot straight with you man... your chances will be pretty slim... even with a masters degree. Assuming you have 120 credits of 2.5 GPA, even if you 4.0 a 30 credit MS program (which is no easy task), you will still only have an overall GPA of 2.8. But your undergrad GPA will still be at 2.5, which may be lower than some schools cut offs.
I would personally recommend you do a year of post bac before doing an MS program. If you take 30 credits of upper division bio and 4.0 them, you will then have an undergrad GPA of 2.8. You could then do a 30 credit MS program and get your overall GPA up to 3.1ish.
Now after all that work... you have to be prepared for the fact that you still might not get in. You might also need to retake the DAT. Below average GPA + average DAT does not bode well for you. So you might need to get it up to the 21+ range. This process will take a lot of hard work and probably at least 2 years of grade correction. You need to look down inside and see if you have what it takes. You could also consider other health professions... nursing, chiropractic, optometry, pharmacy, or podiatry. However, you will still need to fix your GPA before applying to those programs too.
Don't mean to be a jerk, i am just trying to give you some very practical advice. Best of luck!!