Why Ritalin?

Just for cognitive issues? Was this a "Try this and see if it helps" type of prescription?

You may be sensitive to Ritalin. It can cause muscle spasm.

If you are on pain killers for your spine and other injuries, using a stimulant to overcome the slowness of thought is like burning the candle at both ends.

What other meds are you on?

Have you been checked for TMJ? Many meds can cause an inflammation of TMJ. Your symptoms sound like TMJ disorder. I have dealt with TMJ problems for many years, on and off.