Hi, 15 yr old girl here. I am not completely sure of why you feel so guilty, since it sounds like you (with consent at the moment in time, though non-verbal) touched her through her panties. You mentioned that she did not try to stop you or appear to be against the idea, so it sounds like it was consensual in the moment, but you two crossed a line you weren't ready to cross just yet in your relationship. While I completely understand why your relationship with your girlfriend might be awkward or uncomfortable at the moment because of the intimate touching, it's hard for me to understand why you feel so terrible about this incident and are so worried that there will be dire consequences. #1. Though you two seem to regret it now, it sounds like it was consensual. You didn't sexually assault her. #2. You touched her through her panties, so there's absolutely no way she'll have any side-effects health-wise: no risk of pregnancy or STDS/STIs. #3. If someone finds out, which I doubt will be the case because most girls aren't going to talk about things like that unless it's with someone they truly trust to not go around and tell everyone, it may be embarrassing but I don't think there will be dire consequences. However, I really do admire how much respect you have for your girlfriend, and if you feel guilty, I suggest you talk to her about it. No, it's not going to be a fun conversation, but at least then you'll find out how your girlfriend felt and her perspective on this, which may help you figure out how to make it up to her and clear up any misunderstandings. Hope this helps, and best of luck.