What are some side effects from radio frequency treatment to the back of the head. For headaches.?

I had radio frequency treatment for chronic headaches that I have had for 8 years. Every day all day I have headache pain. After my procedure two weeks ago I have more intense pain and numbness in the back of my head. I think the doctor made a mistake because I've had the treatment 3 times prior. I am worried that this is permanent. It is ruining my life as I cannot function due to the pain.