Dear friend,
Because the priest was not there does not reduce the affront that your mortal sin is to God. Going to Confession isn’t just about us; it’s about re-uniting with the Lord because we love Him. Receiving Holy Communion when we are in the state of mortal sin is to commit a further mortal sin and not a loving thing to do.
Get yourself to Confession–even if you have to make an appointment. If it is inconvenient for you to do so, the sin itself if far more inconvenient for God.
You are in our prayers.
Fr. Vincent Serpa, O.P.