Phrost,
I read through most of the responses and didn't see any actual Marines responding to your post. Fact is, if you're solid in PT, not grotesquely anorexic, and your OSO approved you to go to OCS, they're not going to send you home for that. It's a LEADERSHIP evaluation. You go there and dick away your indoc PFT, then you're ass is on the next flight back to Hoboken.
Eat well. Don't make excuses. Hard boil eggs to take to eat during the day when you're "busy". Trust me, as a Marine officer, there is plenty of times where you don't have time.
The height weight standards are a "standard", not a requirement. I think I've been outside of them since I've been in the Marine Corps. Run a first class, no one gives a shit.
Finally, be careful with creatine. Supplements are illegal at OCS. I'm not saying don't take them before, just be mindful of what you're putting in your body. Seeing that you're only a couple weeks out, stop with creatine. It severely dehydrates your body, and since you're going in the summer months, that should be a very big concern. You should start hydrating your body and setting it up for the rigors ahead.
good luck.
Frenchy.