Board Certification in Plastic Surgery is no guarantee that your injector is any good at a particular service. I for one do not believe that botox should be used around the mouth for precisely this reason. I do not recommend that you get more botox to fix this. The service will get better gradually but it can take months. Find someone else for future service.
Yes, your smile looks uneven. I suggest you see your injector and you can have a "touch up" to make you more even. I always encourage patients to return at 2 weeks when all the Botox perviously injected is maxed out before any corrections. If you're not 2 weeks out then wait to be sure the other side has caught up.Best wishes, Dr. ALDO