Am I putting too much thought into this?

I've (20m) been talking to this girl (19f) for a while now and I thought things were going amazing. We go to the same college. Things started off slow then sped up a bit she was always super quick to respond and she was always smiling and she had even asked me to go look at Christmas lights with me which we did then we hung out and talked for a while. She had said that she thought it went well and she had fun. She even called me "Hun" on a few occasions and once called me "hunnybun" now we're both on winter break which we still have another week to go until we go back. Throughout the beginning of break it was super nice and she on multiple occasions said she wished we lived closer together and one time she said she wishes I could come and nap with her. I don't think that I did anything wrong and she certainly didn't tell me that I did. I told her yesterday that I had gotten a new motorcycle helmet and that since I have an extra that I could take her for a ride in the spring and she said that sounded fun and she would like that. Now it just seems like she isn't trying to respond to me as quickly and that the conversation is running dry. I can only think of three scenerios first being that I did something wrong, second is that she just isn't that into ke anymore, or third that it might be her time of the month