You're pretty much right at the median for matched students so as long as you don't have some glaring red flag (and maybe even if you do), I don't see how you wouldn't be fine, especially if applying broadly. (source: Charting Outcomes In The Match, NRMP, p. 9)
231 is a great score. I really don't understand why you're beating yourself up. I've been studying my ass off for Step 1 and can honestly say I'd be honored to have a score like that. If gas is what you want, set yourself up for success. Apply to 20+ progs if you need to; though I'd put my life savings on you getting in even if you didn't.
As an aside, damn...wouldn't it be cool if you could bet on such a thing? That'd be one hell of a casino game.
Good luck, and don't waste time being down on yourself. My guess is this time 5 years from now you're putting me down in the OR for back surgery.