No, your theory isn't right, and the reason is because in heaven we will be in God's presence forever -- and no sin can exist in His presence. God is absolutely holy and pure; as the Bible says, "Your eyes are too pure to look on evil; you cannot tolerate wrongdoing" (Habakkuk 1:13).
Yes, we will be perfect and without sin in heaven. I can barely imagine this, but it's true, and this should encourage us every day. Think of it: Not only will all wrongdoing be banished, but everything that happens now because of sin's grip on this world will be gone forever. Illness and death will be destroyed; sorrow and disappointment will be no more; the faults in our characters will be transformed.
All of this is possible because Jesus Christ took all our sins away when He died on the cross for us. He not only came to forgive us; He also came to cleanse us of our sins and make us fit for heaven. Is your faith and trust in Him?
Heaven is our hope, but in the meantime, God wants us to live for Him right now. Is this your goal? Make certain of your commitment to Christ, and then rejoice that someday you will go to be with Him forever in heaven -- fully cleansed of every sin, and perfect in His sight. In that day, the Bible says, "we shall be like him, for we shall see him as he is" (1 John 3:2).