All believers are part of the priesthood. It is God who forgives; men are merely the conduit. Also, a man can go directly to God for forgiveness without the conduit of other men. I am sure many a lonely man has confessed on his deathbed all of his sins, whether was was stranded at sea, lost in some wilderness, or left in some prison cell to rot.
I have no beef with the Catholic Church, per se, but when you post this kind of stuff which might cause people to question whether their sins were forgiven or not merely because they did not seek out some Catholic priest, it’s exasperating to say the least; and, frankly, mean.
Since, according to Scripture, our Lord entrusted the power to forgive or retain sins to His Apostles and their followers, why not follow Chris's instructions? How do you know if your sins are forgiven?