Tmj flare up a week ago and now a tender bump on lower left jaw line. its under my first molar, not on gums but on my actual jaw line. tender touching?

Muscle or lymph node: This could be some muscle tension related to the TMJ problem in the Masseter muscle. Alternatively it may be a lymph node responding to some infection in the head region. If it persists more than a week or so have you dentist take a look. For information on TMJ check my webpage here... http://www.laserdentistbaltimore.com/tmj-therapy/

Visit the dentist: Tooth/gum infection can further spread to other parts of the body like jaw bones and sinus. It also can result in systemic infection. Therefore, dental treatment is a must. Keep a good oral hygiene and call for appointment.