What do i do with the swelling. my gum swollened at the back of the molar and it's not wisdom teeth that cause it because i removed last year.

Have it examined: It may be food impaction, periodontal pocketing, or even an abscess from a necrotic nerve. Once the cause is determined, your local dentist will determine the proper course of care. Feel better soon.

Gingival abscess: I suspect that you have an abscess in the mouth, more specifically in the gum. See your dentist for evaluation and treatment.