First, call 911 and remain at the scene until law enforcement arrives. The Boston Police Department or the Massachusetts State Police will secure the scene. While you’re waiting, take pictures of the scene, any property damage, and any visible injuries. Get names and contact information for the other driver and any witnesses, and exchange your contact and insurance information with the other driver. Get medical attention at Mass General or another area hospital, and schedule a follow-up appointment with your doctor. Notify your insurance company that you’ve been involved in an accident. Most importantly, call a lawyer as soon as possible.