Helping Find My Fire?

I play Tennis for my high school, but I often find myself asking myself how bad do I want to win. The answer I always come up with is "not bad".... I know I was more competitive as a young kid, and its a key aspect for sports! Ugh.. How can I rekindle my competitive spirit? Is it a medical problem? I have a meet today after school, so any quick answers would be greatly appreciated! Thank you!