Sinus infection and missed period

I have had a sinus infection for about 2 weeks now and have recently been treated for it. Last month my period was late a couple of weeks but I had been under a lot of stress. I was supposed to get my period 2 days ago and I haven't, could my sinus infection be affecting my period? My boyfriend and I have had sex the last couple of days but we've been safe about. Would if be smart to take a pregnancy test or should I wait a couple more days to see if I get my period? If anybody could give me advice that would help a lot. Thank you!