8 days ago, while I was cleaning my bottom teeth in the mirror, suddenly a small pulsating lump appeared in the middle of my bottom lip that was NEVER there before. I actually saw it arise, with no trauma/injuries/contact-exposures occurring on either of my lips while I was in the mirror, nor anytime prior to that. After examining the lump (that is still present), which pulsates to my heartbeat, I am worried that this is a protruding artery that will not subside. What can be done to fix this?