Go for xray May be you need immediate Endodontic treatment

Looks like abscess in the picture. You need to get one x-ray done followed by endodontic treatment. Consult a doctor online for more details.

By looking at attached photographs it seems like your tooth is infected and their is abcess formation which require root canal treatment. X ray is helpful to diagnose it properly. Root canal treatment along with medication and hygiene, it can be cured completely. Betadine gargles or betadine mouthwash you can use.

Hello Sir,     From the given clinical photograph it seems that, your tooth needs endodontic treatment as there is formation of  abcess & it can be confirmed by the small radiographic image i. e IOPA  of the concerned tooth .    

Hello. Firstly, it would be advisable to get an Xray done (OPG will be better, if not then atleast IOPA). Also, a thorough clinical examination especially of the offending tooth, upper jaw, palate and maxillary sinus is required. Therefore, I will advise you to go to the nearest Oral and Maxillofacial Surgeon for a more comprehensive examination followed by approximate imaging (atleast OPG) to come to definitive diagnosis and treatment.

Hello, It can be treated with root canal treatment. The abscess will be drained and cleaned with medicaments.