Is my salvation still valid if I later change my views? I was raised Christian. I was told of the salvation that comes if I only agree to accept Jesus into my heart. I did. I was a devout Christian for years. 

After a while I began to have doubts and now identify as an atheist. My question is does the salvation that I agreed to still stand? I was told that although I will continue to be imperfect and sin, I am in the clear as I've accepted forgiveness. Does that include the sin of no longer believing?

I understand that Catholics view salvation differently and their interpretation of salvation requires continual practice, but most protestants mostly require a simple acceptance of Christ's redemption. Under protestant rules, does my acceptance of Christ's redemption still stand although I no longer believe in him?