Can sinusitis cause painless facial swelling too?

Unlikely: If sinusitis is the cause , this would be a very serious complication which would make you quite ill. Your swelling is more likely from angioedema (swelling in the subcutaneous tissue). I don't know how long you have had it but if the problem has just started a few days ago. antihistamine may help. If the problem persists for more than 2 wks, see an allergist.