What Causes Tingling In Lower Lip With Inflammation On Side?

My lower lip started tingling a few weeks ago. I noticed it was also red on the left side. A freind told me I was getting a cold sore (no history) so I started using Abreva. It seemed to get a little better and I stopped. Then it would flare up again. It never materialized into what I thought a cold sore looked like. Now it feels like the interior of my lip is burning from side to side.