If you suffer from Stress, Anxiety and depression over guilt is there anything that can help you?

When I was a young teenager I done something now as an adult I feel guilty about it, part of me has good options wrote down and why it’s ok but then my brain tells me the bad things about it and now I just can’t enjoy my life anymore, I live in fear that my body and mind is breaking down and I can’t remember or concentrate on things the way I used to, I then don’t know if it’s because of this guilt thought or because of an underlying condition because anytime I’m in a happy state of mind and a symptom shows up I go back into thinking about the guilt, I’m a good person with a young family and I’m not enjoying life the way I should but I’m sacred to talk to someone about it even though it was years ago