Please Help ASAP! Thank You?

A couple of minutes ago... A girl about 15 or 16 years old came over to my home and was talking to us about how she had to find out or at least think about what she was going to be in the future for a contest.. so i told her i was a student, etc. and what my parents did...then she said she had to prove that she talked to other people and that she needed to collect points to be entered to win money... she gave me a pamphlet with magazines on it and how many points each was worth... i politely declined telling her that we had enough magazines and she walked away looking sad... and gave a sighing "okay" the problem is... thinking she was an innocent schoolgirl i left our door wide open... could she have been looking around for something she (or somebody older that she could tell) could steal? i dont know if im just being paranoid... but i feel a little uneasy that i just left the door open like that. what should i do? contact the police? (probably not) or should i just forget about it??