Congratulations on making your first level! You don't have a bad sense of decoration, good building placement. It's really long though.
Quick note: Infinite Boost makes speedrun strategies very boring for most players. Unless the entire level is enclosed, the car could just fly from one point to another, so it's usually better not to have infinite boost and make sure there's enough cooldowns/checkpoints on track fullboost it.

Anyway not bad for a first level!