It is not unusual that after prolonged or complex dental treatment for your mouth may feel bruised and sure for a day or two. Apart from the dental treatment itself this may be an after effect of the local anaesthetics or just from keeping your mouth open for a long time.
You may initially find it difficult to close your teeth together in the normal way, and your gum may feel a little sore and swollen. These effects should quickly subside within a few days.
If these symptoms do not settle it is important to return to the practice for professional advice and treatment if necessary.