My Smile Looks Like the "JOKER SMILE" After a Face Lift?

I'm not sure what you mean by the description but if the smile after healing from the operation is in somewhat different there is a problem. You should take up your observations with your surgeon.

I would want to see pictures but midface lines or joker lines are common after facelifts. It has to do with the way the tissue under the skin has been removed, they do tend to settle. Speak to your PS their are things to do at this point if you are unhappy

A "Joker" smile can occur when the muscles of the face are tightened or when the skin is lifted close to the corners of the mouth.  These are very different techniques, but your surgeon should be able to tell you what he did that caused the change. For example, in a deep plane facelift, the muscle that supports the corner of the mouth (called the Zygomaticus major) is tightened.  This can pull the corner of the mouth. If you are getting compliments about your improved looks, the change in your smile is probably something that you notice more than others do. Discuss with your surgeon, but don't let this interfere with you enjoying your result!