Accidentally got a boner when a [F] friend clung to me at Knott's Scary Farm

To clarify, we went with our friend group and i don't have feelings for her, but I've never been in a relationship before. So, the physical touch "awakened" something in me and I felt happy. In my head, i was like "so this is what's it's like..nice" (guess i'm touch starved lol?) Thankfully it was dark, but i involuntarily got a boner when she initiated and clung to me and another friend when we entered the scare mazes. She most likely didn't notice, yet i still feel guilty. Sorry!