Well, you should not confess it again, because God has already forgiven you - and if you did confess it, you are saying you know better than God does on these matters, and that would surely be a sin.
It’s quite possible that you don’t question whether God has forgiven you, but rather that you still feel remorse. It’s certainly fine and wonderful to discuss the matter with a priest, to hear his words on how to get over it, but that’s different than a confession. The answer lies in prayer, maybe reading the Bible where we learn how much God loves us, and knows what retched sinners we are - God loves us infinitely! Knowing that, and praying, will hopefully get you on a path where you can fully accept God’s forgiveness.
One last point - in today’s devotion in the Magnificat, there was a great sentence that was very useful to me - “Live life today, and leave the future to God.” The same applies to the past.
Good luck!