How do you know if you are a Christian who is saved?

I’m unsure if I have been. I got baptized when I was 19, I don’t believe I was ready to surrender my life over to Christ back then although I thought I was. I recently committed a sin twice that goes against the 10 commandments. I feel very guilty. I confessed my sin and repented but I’m not sure if it is enough to make it to heaven since I did it twice. I felt bad the first time, didn’t think I’d do it again, but I did and feel even worse this time. Now I know I’ll never do it again. I heard if you are saved you would never commit a bad sin like this. For years I thought I had a strong faith, but i realized the things that I’ve been doing for years have not been Godly. I feel like my guilt is keeping me from pursuing a relationship with God now and asking him for his forgiveness because I feel like I do not deserve it and should be punished and live a miserable life. I understand that God can forgive all, He forgives all that is repented but how many times can you do the same thing regardless of forgiveness and still make it to heaven? I was sure of my faith until I committed these two sins. Now I’ve been wondering if I’ve ever been saved/have had faith at all. Now I know that I am ready to commit my life to Christ but if I’ve already been baptized would there be a point in doing it twice?