This just means your physical therapist has extensive experience! 

Prior to the 1990's, most entry-level physical therapy education programs were Bachelor's Degrees.  PT programs advanced in the 1990's to Master's Degrees.  Many physical therapists with Bachelor's Degrees went back to school to add a Master's, and many with Master's went back to add the Doctorate.  Regardless of your PT's entry-level degree, all clinicians add extensive continuing education annually.

While the earlier degrees are now phasing out, you will find that all physical therapists must keep abreast of current research evidence and best-practice in order to maintain their license to practice.  Either way, you're in good hands!