It sounds as though swelling is the key component of your asymmetry. When you see your surgeon, show him/her your concerns and I am confident that they will say that you are healing well.
If it is a nerve injury to the motor nerves around your mouth, they normally heal without any further intervention.
I always recommend that you back to see your surgeon for an opinion. You probably have swelling that is causing your findings.
In the event that one of the branches of the facial nerve became stretched it is very likely to recover. So, your prognosis should be excellent. Good luck.
There would still be some expected swelling present at 10 days after a lower facelift and this can definitely make the face appear uneven. It will take a few months for the swelling to resolve and in most cases, the uneven appearance will improve. Be sure to discuss this issue with your surgeon so that your progress can be monitored.
It is not uncommon to have some facial animation asymmetry post-op that is often due to swelling. Usually this improves with time, but follow closely with your surgeon.