Don't let anything - your shame, your feelings of guilt, your doubts or anything else - keep you from God. The Bible's words are true: "You are forgiving and good, O Lord, abounding in love to all who call to you" (Psalm 86:5).
I suspect your real problem is that you don't feel you are worthy to come to God and ask for His forgiveness. And the truth is - you're right! You aren't worthy - and neither am I. The Bible says we are all sinners, and the only thing we are worthy of is God's judgment. The Bible says, "There is no one righteous, not even one" (Romans 3:10). No matter how good (or bad) we are, we all fall short of God's standard - which is perfection.
But listen: God still loves us, and He yearns for us to be cleansed of our sins and to become His children forever. How do I know this? I know it because God sent His only Son into the world to die for our sins. If you or I had been the only person on earth that needed to be forgiven, Jesus Christ still would have been willing to die for us. The Bible says, "This is love: not that we loved God, but that he loved us and sent his Son as an atoning sacrifice for our sins" (1 John 4:10).
God has promised to receive all who sincerely come to Christ in repentance and faith - and He cannot lie. Don't carry this burden another day, but confess your sins to God and trust Christ for your forgiveness without delay.