Rinse with salt  lukewarm water. See your dentist to check the reason. The earlier, the better . Delay in getting loose gums treated can lead to loss of tooth

From your description it seems you have periodontitis which can be treated with scaling n polishing. V8sit periodontist who specializes in gum disease treatment. You are very young just 21 year old start treatment as soon as possible so that periodontitis won't progress further.

Swollen gums and mobility of teeth is due to Periodontitis.  U need to visit d dentist get teeth scaling done  first . After that depending upon d severity u may or may not require flap surgery .

Swollen gums and teeth getting mobile (loose) is a sign of infection in your gums which is routinely caused when food gets accumulated between the teeth and gums and is not cleaned out. This problem of swollen gums can be treated with a scaling (deep cleaning) and change of oral hygiene habits and the loose teeth should be examined clinically and should be monitored periodically.