My period is three days late

A few weeks ago my hubby accidently cum inside me (just a little) we always used the pull out method.

We been having sex for 9 months almost everyday and he has never cum inside me.

Anyways I'm having low back pain that I usually get when I'm on my period. I'm moody, eating alot and having light discharge.

All those happen to me when I'm on my period.

Should I worry or is it just running late?