Sinus Discomfort Post-blephroplasty - Will It Go Away?

There is no relationship between sinus pain and eyelid surgery.  These are separate and unrelated processes.  I would recommend that you see you Primary Care Physician for guidance and an Otolaryngologist if the problem persists.

Sinus pain after blephroplasty is not normal as the two are not related. See your surgeon and if he thinks it is sinus pain, he will refer you to an ENT surgeon.

I think that it would be a mistake to assume that the sensation you are attributing to the sinus is typical.  It is not.  It may or may not be related to your eyelid surgery.  I think this needs to be worked up.  You should certainly let your surgeon know what is going on.  It is reasonable to have them assess you but you may need to also see an ENT for this issue.