It's called operculum and it's a flap over the erupting wisdom tooth. You can rinse the area with mouthwash and keep it clean . This will vanish once the tooth erupts properly . Incase it doesnt , please visit the dentist and get x-rays to make sure it's not impacted . You can even get operculectomy done to remove the overlying flap.

Hello This is very normal at this age this is due to wishdom tooth eruption no need to worry just maintain cleaning at that area some times it hurts  aloot swelling is also seen sometimes if that happens immediately consult to near by dentist meanwhile just make that area clean as much as you can

It's normal , ur wisdom tooth is erupting and thus u may get pressure pain . Not to worry keep that area clean ,do warm saline gougles 

It’s the normal tissue that once covered your wisdom tooth . The moment your wisdom tooth starts moving up so do the tissue about it . Due to this, it often gets sandwiched between upper and lower teeth whenever you chew or bite . Persistent trauma to it might lead to pain and ulcer . Many a times food gets lodged between it and the underlying wisdom tooth . Well , it’s a normal in a way but it can become painful over a period of time .