You must discuss all your sins with your priest. Because confession is more than just telling your offenses and getting absolution. The priest is seen as a physician and you’re the patient. Not only are you asking for healing, but also preventive measures. Even when I started attending the Ukrainian Church, I still went to an RC priest for confession because the priest knows me well. At first I was shy, afraid and hesitant. Then I finally had my first Byzantine confession (in a confessional, nonetheless

) and it was the best confession I ever had. I think I was in there for like over half an hour, and the priest listened to everything I said, and he address everything I confessed one by one and giving me wonderful advise on how to become better and avoid sin in the future.