As some of you may know I’m a high school boy struggling with lust, especially masturbation and to a lesser extent pornography. Recently I’ve been on a very successful purity (no porn/masturbation/indulgence in lust) streak at about a week and a half. However, last night I had trouble going to sleep and indulged in lustful thoughts to help me. I knew indulging in lustful thoughts is grave matter but for some reason I felt like it wasn’t mortal for me at that point, for some stupid reason I don’t remember now. I also began stimulating myself but had no plans on reaching orgasm and indeed didn’t. This went on for some time - between several seconds and a few minutes - before I became more aware and stopped because I knew it was sinful. Now I’m wondering whether I committed a mortal sin or not. I definitely came into the near occasion of sin at best, but I’m not sure whether to treat this as mortal, venial, or just a close brush with sin right now. Could somebody more knowledgeable than me give me some insight?