Here are 3/10 of God's ten commandments.
Thou shalt not lie (You are a liar, if you have told one lie)
Thou shalt not steal (Even if you accidentally took home a pencil or pirated music you are a theif)
Thou shalt not lust(For if you look at a woman with lust, you have commited adultery in your heart)
If you have committed even just one of these crimes, you are going to hell, because God will not allow liars, theives or adulterers into his perfect kingdom. Ontop of that, if you are in court and guilty of a crime, no good judge can let you go no matter how many good works you've done. If you've murdered someone, it doesn't matter if you saved a thousand lives, you will pay the fine.

Romans 3:10
As it is written, There is none righteous, no, not one:

Hebrews 10:26-27 For if we sin willfully after that we have received the knowledge of the truth, there remaineth no more sacrifice for sins, But a certain fearful looking for of judgment and fiery indignation, which shall devour the adversaries.

Ephesians 2:8
For by grace are ye saved through faith; and that not of yourselves: it is the gift of God: Not of works, lest any man should boast.

John 3:16
For God so loved the world, that he gave his only begotten Son, that whosoever believeth in him should not perish, but have everlasting life.

Corinthians 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.

Proverbs 28:13
He that covereth his sins shall not prosper: but whoso confesseth and forsaketh them shall have mercy.

Matthew 9:13
But go ye and learn what that meaneth, I will have mercy, and not sacrifice: for I am not come to call the righteous, but sinners to repentance.

As a christian, you are not promised a happy care free life, you are not a christian for joy and peace. You are a christian so you are not damned to hell for sinning against a just and holy God.