Can the nerves have been cut while having cataract surgery that would cause saggy and puffy skin under eyes?

Thank you for your post. Without seeing pictures of your eyes, I am somewhat limited in my assessment. What you are most likely experiencing is some post-operative swelling around the eye that is making your lower eyelids look puffy and saggy. This would not be the result of nerve injury. How long ago did you have the procedure? With time the issue should resolve.