I found that the further I go with Christ the more appalling the things I did seem to me. As previously stated, I don't feel guilt about it, but it does lead me to some wonderful praise and worship times when I think about what God called me out of.
I know that condemnation thing - Satan does try it on every once in a while, but we choose to listen to God and immerse ourselves in scripture to renew our minds:
"Therefore, there is now no condemnation for those who are in Christ Jesus, who do not live according to the sinful nature but according to the Spirit. " Rom 8:1
We know why the enemy tries it on - because he is already guilty and will reap what he deserves:
"the prince of this world now stands condemned." John 16:11
1 John says some pertinent things about condemnation:
"Dear children, let us not love with words or tongue but with actions and in truth. This then is how we know that we belong to the truth, and how we set our hearts at rest in his presence whenever our hearts condemn us. For God is greater than our hearts, and he knows everything.
Dear friends, if our hearts do not condemn us, we have confidence before God and receive from him anything we ask, because we obey his commands and do what pleases him. And this is his command: to believe in the name of his Son, Jesus Christ, and to love one another as he commanded us. Those who obey his commands live in him, and he in them. And this is how we know that he lives in us: We know it by the Spirit he gave us. " 1 John 3:18-24
As we grow as Christians, we become more able to discern God's voice and we learn how to separate what God is saying to us from the enemy's attacks. The fact that you are feeling this anxiety may well be the Lord testing you as a way of leading you deeper into His truth - if you were still hypothetically in sin and feeling comfortable with it, you wouldn't feel anxiety about it. So press on - you're on the right track. Don't let memories paralyse you and make you ineffective. It might be a good idea to memorise suitable scriptures so they well up in you and refocus you when this kind of thing happens.
Jules