Vns and ultrasound therapy

Yesterday I started physical therapy due to severe lower back pain. My neuro recommended the physical therapy. His theory is less pain reduction in seizures. I have a vns but failed to remember ultrasound therapy is not allowed. The therapist started the ultrasound and I started feeling electrical shocks. I told the therapist having painful shocks. He told me probably the heating of ultrasound. The shocks finally stopped. I went to physical therapy in December of 2016 didn't have any problems with ultrasound. The reason I quit therapy at that time was due to grand mal seizure. The therapy too hard for me. My neuro wants me to do whatever it takes to get through the therapy. I am afraid have damaged the nerves in arm, shoulder, and vns area. I am also afraid have damaged the vns. When I left therapy my arm was heavy, shoulder, vns area feel funny. I still feel the same today. I plan to call my doctor Monday but wondered if someone might have experienced my same problem. Thanks.