Period 3 days late

Hi everyone so we have been ttc for about 7 months now. Well this month a tool a break t became too much for me to handle plus it was my birthday month! Well my period is 3 days late and no signs of coming at all usually I get pms symptoms but nothing. I took a test but got a bfn (not FR) I’m not until AF arrives but not sure what to do?? Any ideas?