Lastly, think about what should come next, i.e., what now? Did you like the song and style you did? Are you doing too many of this kind of song or do you need to explore this area more? Was the piece too much for you or too easy, too high, too fast, too comfortable? Where did this performance put you towards your long-term goals, the musician you want to be, and the music you want to play. Based on how you did, (Dare I say it?) are you practicing enough? Look at what you did and consider if you're progressing at the rate you want, if you were to extrapolate it out over the next several years.
Improvising makes you more in touch with your instrument and voice, regardless of the style. Many classical composers were great improvisers.