I just had a composite filling done about 8 hours ago, and it hurts chewing, and even when i move my mouth. it was polished there. what could be wrong

Multiple issues?: There are any number of issues that could be effecting your tooth. Your bite could be off due to the filling being high, the filling could be deep and close to your tooth's nerve, the injection site could be sore, another tooth could be acting up, some rare occasions one could have a reaction to the composite, but bottom line, your dentist is best equipped to diagnose and solve your problem.

Common problem: After having composite filling, there is sometimes an unusual kind of sensitivity which can occur. It is not clear what causes this, though it seems to be related to possible bonding failure or cavity contamination. Replacing the filling with another composite filling will usually eliminate the problem. Schedule an appointment.

Recent filling: It is normal to have some discomfort after a filling especially at the injection site for the local anesthetic The pain when chewing could mean that the filling is a bit high and needs to be adjusted. Contact the dental office and go back in for an adjustment--will take a few seconds. If the filling was deep the tooth may take a few days or weeks to calm down.

Have it checked: If filling is only slightly high tooth can be painful. If cavity was large, then the surgery to remove the decay can irritate the tooth's nerve. If cavity was deep, nerve may be infected. Call your Dentist got a reevaluation.