go t doc immediately...he will prescribe antibiotics an painkillers ...after sweeling subsides an x-ray will be taken ....den it can be decided weather it will be extracted or saved by root canal treatment

The swelling is mostly because your tooth might be affected with infection called pulpito,which need root canal treatment,before the symptoms aggregate even more ,try to visit a dentist near u

It seems that your tooth is affected by Irreversible pulpitis and will require root canal treatment. The swelling is because of the spread of infection from the tooth confined to the bone. The practical implication of this finding is that you should not delay this treatment further before the symptoms can aggravate. Search for a dentist in your vicinity using Practo and try to schedule an appointment as soon as possible