If you are having that negative a reaction, the PT may be doing too much or working too hard. In my experience, PT that caused too much pain never did me any good, in fact it made me worse. Overdoing PT following surgery was one of the contributing factors in forming scar tissue. That scar tissue has been debilitating for 6 years now.

Usually the PT will want to know how you're reacting and can alter course accordingly.

Good luck.