Haha what timing. I just took the MCAT last Friday.
I applied for accommodations for my pump/food too but they rejected my claim because I didn't make it early enough (I didn't realize you had to make a request for a pump). I called them multiple times to figure SOMETHING out, but they were absolutely not budging so my only choice was to switch to shots a few days prior or risk trying to sneak in my pump. I was pretty livid that I had to have this increased stress during a super stressful test already. Kinda retarded that the people who let you become doctors don't want you treating your diabetes, no?
Come to find it out didn't matter. I got to testing center and they asked me to empty my pockets so I took everything out and left the pump in but said "I wear an insulin pump because I have type 1 diabetes". I don't know if all the testing site people will be cool like this, but I showed it to her and she just said "ok". I had my meter and glucose tabs with me and left them in the lockers you're provided outside the testing room. I just tested beforehand, tested during breaks, went low once and just ate some tabs and lowered my basal, otherwise diabetes wasn't a big issue.
If I were you I would just make it seem like you can't take off the pump once you get to the testing site without making too big of a deal about it. If they're a-holes and make you take it off then just reconnect during breaks. That was my plan B if they made me take it off.
My practice test scores were all over the place too. Don't worry about it. If you get out of a section and feel like you did awful just remember that everybody did awful if it was a hard section. I don't really have any test advice other than answer EVERYTHING and really pay close attention to VR, I feel like half the questions there are just trying to trip you up into making stupid mistakes.
My test was really heavy on sound stuff in PS (which I conveniently decided not to study for), both my writing prompts were politics oriented, and there was a lot of kidney and digestion stuff. PS raped me, but I knew that was gonna be my weakest section. And all this advice could be completely useless because yours will probably be completely different, BUT if I had the chance to go back I would have studied more those couple topics.
My only other advice is to sleep well, eat well, and keep your blood sugar rock solid before the test so you don't have to worry about it. If they give you the OK on your accommodations request then awesome, but dont waste any time testing during a test, just eat the second you feel low.
Good luck! I know it sucks. It was an awful summer for me too, and you'll never leave that test feeling great, but just know that everyone else feels the same way. Let me know if I can help with anything else.