Placement of the patch can make a difference to RSD pain. Also, the directions do tell you not to put it in the exact location 2 weeks in a row if you didn't notice it...and my experience concurs that this is good advice.

Be careful when you're driving if your pain levels spike on the trip home, since elevated pain levels can make you lose focus on the road. It would be a good idea to have a passenger review your driving ability since we're not always able to judge how are driving performance has declined.