If you're in a good "box" then you'll be fine, if not then it's any ones guess. Now the question is what determines a good box. I would check out a few boxes i know your area before committing to one. If the coach doesn't emphasize things like proper form before intensity, leave. If the box doesn't have anything for active recovery i.e foam roller, lacrosse balls etc leave. If they dont emphasize a proper warmup routine, leave. And last but not least whats the programming like. If they don't emphasize building strength then head for the hills. The vast majority of injuries in crossfit (or any where else for that matter) occur because people who are not strong enough are doing these movements at high intensity. And if they follow mainsite programming then it's just a waste of time.