Stop and rest. When using the device causes pain, stop doing whatever causes pain and rest. This will give the body a chance to heal, and reduce the risk that the injury will become a chronic problem.
Stretch and massage the area. Minimizing muscle tension in the affected area can resolve the aching sensation and improve flexibility.
Seek professional help. If the pain becomes unbearable and causes difficulty with daily tasks, consult a physician. Proper treatment and management of repetitive strain injury can reduce long-term consequences.