It's much easier to love a sport when you're the team MVP and things are going well. Success is what makes things fun. However, every sport will have challenges along the way and track will, too.
If you want to run track because you love to run and would still love it if you weren't the state champ, then that's probably where your heart is. However, if you're leaving baseball because you've hit a bump in the road and don't want to risk struggle or failure, be sure to take some time to think it through.