Yes you felt something I imagine a 13 year old tingling twitch but did not know how that would correlate with girls...That came later...
Oh nooo, no, no, no. At 13 I knew exactly why I liked girls and it was all about the girl parts. Most fathers know when their male children are starting to undress the softer sex mentally, while most mothers are clueless. I guess it's a marternal thing to think young boys are more innocent than they really are.