guilty

So I've been dealing with feeling guilty alot lately. Not just cause I used the word alot in writing. The guilt is not the prevailing thing in my mind but it sneaks up on me when I am not prepared to deal with it. Its a weird guilt - I know that the Lord is my savior and he counts me pure and blameless, that I don't need to prove that I am good enough or have to do anything. And the guilt isn't just about faith things. Its over things I did 10 years ago as well. Is this what is called having a noisy conscience? Or do I have alot of repenting and changing that needs done?