Yes this is not an uncommon problem. It usually gets better however if not gone at 6 months it may not go away. See a oculoplastic surgeon. Find one at www.aao.org Surgery to lift the lid is sometimes indicated.
JCH MD
No droopy eyelid (ptosis) is not a cause of post cataract double vision.
JCH MD
Can repairing the droopy eye lid also fix double vision caused by the lens implant?