If there is anything that shakes my faith in God or supernatural entities, it is making mistakes...
You are not alone. The Apostle Paul had the same problem. Read Romans chapter 7. Read it a few times.
When you were born again you received Christ in you.
Col 1:27,
To whom God would make known what [is] the riches of the glory of this mystery among the Gentiles; which is Christ in you, the hope of glory:
Furthermore, that Christ in you
makes you as righteous as God himself.
Rom 3:22,
Even the righteousness of God [which is] by faith of Jesus Christ unto all and upon all them that believe: for there is no difference:
Don't argue with God! If he said your are righteous, you are righteous. It does not depend on your feelings. God said it, that settles it!
However, you still have your flesh and, as Paul said in Romans 7, that flesh will continue to blow it day after day.
Jesus himself said something revealing about the flesh.
John 6:63,
It is the spirit that quickeneth; the flesh profiteth nothing: the words that I speak unto you, [they] are spirit, and [they] are life.
Paul also said there is no good thing in the flesh (Rom 7:18). Unfortunately, for the most part, churches do not believe Jesus or Paul on that point. They insist on preaching about the necessity to work on your flesh and somehow make it better. But how can you do that if there is no profit or no good thing in the flesh? No wonder you feel so bad! You, a victem of church doctrine, are just beating your head against the wall.
God did not redeem you by somehow making your flesh better. He's not stupid. Instead He created a whole new you.
2Cor 5:17,
Therefore if any man [be] in Christ, [he is] a new creature: old things are passed away; behold, all things are become new.
Gal 6:15,
For in Christ Jesus neither circumcision [i.e.following law] availeth any thing, nor uncircumcision, but a new creature.
This new creation is the Christ in you of Col 1:27. The born again child of God therefore has two natures, flesh and spirit. God ignores the flesh and loves the spirit like nobody ever loved.
Rom 5:13,
For until the law sin was in the world: but sin is not imputed when there is no law.
Jesus ended the law, so the law is gone. Because of that, whenever your flesh blows it (which happens often), God does not put it in your ledger. If He did, you'd hardly be as righteous as God, which I've showed that you are.
God doesn't look at your flesh. He looks at the Christ in you and that is where your perfections and true self abides. You are the absolute apple of God's eye. Align your thoughts with God. He knows better than you.
The more you see how God sees you (by studying scripture), the more Christ like you will become. It will be quite natural and effortless.
2Cor 3:18,
But we all, with open face beholding as in a glass the glory of the Lord, are changed into the same image from glory to glory, [even] as by the Spirit of the Lord.
Look at the Christ in you and forget the flesh. I hope this helps you see how wonderful you really are in God's eyes. It's best not to argue with God no matter how you feel or what you think about yourself. Father knows Best!