Have Cervical Hyperlordis And Other Spinal Issues. Been Diagnosed With TMJ. What About Dizziness?

I have cervical hyperlordis and other spinal issues,but have also been diagnosed with tmj .My dentist has given me a splint to wear at night,and it caused a severe flare up of pain in my face, neck ,back and shoulder.After readjustment I tried wearing it again,this time apart from acute pain in the jaw I had a bout of dizziness,the room was spinning.Is the splint/mouth guard causing this?