If a bracket has broken off your tooth it will need to be re-cemented onto the tooth. Contact your orthodontist as soon as possible to make an appointment.
If the wire has broken it will need to be replaced or cut as soon as possible please contact your orthodontist to organize an appointment. Broken wires can often be sharp so it is recommended to use some of your orthodontic wax to cover the sharp end until it can be attended to.
For any other sharp areas causing pain use your orthodontic wax to cover the area causing you trouble. These areas will usually resolve after a few days. If you are concerned you should contact your orthodontist.