Welcome to the Forum.
I wish you the most of success and by doing so from an old medical old timer my truthful suggestion, advice if you like..
First, attempt to get the EMT out of your head if you really want to be a physician. Not that it can't be done; but too many get bit by the "EMS" bug and will never continue. My suggestion is to work in a hospital lab or as an ER tech where you will be exposed by more in-depth controlled environment. You will also make contact(s) of physicians (which you will want recommendations from) and the hours, pay and conditions are much better than in EMS. Many will attempt or describe on how they are accomplishing this, but see how many actually return here and describe how they were accepted into medical school or are currently in medical school....
(Please do not take personally) but... I wish I had a nickel for every pre-med student that I have taught, worked with, or even discussed on EMS forums.. A hint.... being an EMT does NOT assist or advance one getting into medical school in fact sometimes, I have seen quite the opposite occur. Again, many get bit by this horrible EMS bug and do to numerous reasons and excuses, somehow never complete their goal. It is quite hard to study at a busy EMS, and finding slower ones that pay decent is difficult to do.
I realize your school load is difficult and attempting to bump up your numbers for MCAT, one needs to be focused and attentive. That is a full load itself. My personal recommendation is get exposed to medicine that will accompany your studies, learn a little and can forget about work off duty, so you can truly focus on your studies.
Again, it is not that it can't be done, just rarely it occurs that someone that works in EMS continues on or is able to focus upon the studies, goals, etc.. as well the pay sucks and one can make it better doing something else.
No, I am not against EMS by far.. but, that is not your real goal. I much rather see you become a darn good physician that will be able to change this profession.
Good luck!
R/r 911