Hi. My Wife Menstural Date Is 9th This Month. We

Hi. My wife menstural date is 9th this month. We had unprotected sex on 28 evng last mnth. But iam sure i pulled out in time. My wife had ipill to be on safer side on 3day tht was 31st morning. She has a tendency to start period 3-4 dayz prior to last cycle date. But till now she has not got it. Shez having back ache nd stomach aches and weakness nd we are tensed now . Please suggest are we in safe zone and is it just anxiety thats taking a toll on us?