Botox-injector hit demandable nerve two years ago, can anything be done to correct damage? (photo)

I had botox in my chin 2 years ago. I felt a sharp pain at the point I of injection near my left mandible nerve. About 4-5 months after injection I noticed it impacted my bottom lip. The left side of my lip appears to poke out when I talk and smile. When I smile without talking, the left side does not pull down as far as the right but prior to the botox injection it did. My smile is now crooked. I am assuming my nerve was damaged. Is there anything that can be done to correct the problem?