Whats wrong with my elbow?

Earlier today I was running for not even 5 minutes but when i got home i noticed my elbow was sore. Honestly i don't run that often but it has never happened before. It doesn't hurt at all it just feels slightly sore when i straighten it out to much or bend it back. It doesn't restrict movement or anything I can move my arm just fine I'm just wondering why it feels like this all of a sudden.