A MEB cannot be self-initiated. Your command, military doctor or personnel administrators (HRC) will have to initiate a Medical Evaluation Board (MEB).
The Army may first do a MMRB, which looks to see if you are fit to do you MOS duties or perhaps other duties you are or can be made qualified to do. I am not to smart on this process.
A MEB will see if you have any medically unacceptable conditions per AR 40-501 chapter 3. If so, you will be referred to a Physical Evaluation Board (PEB).
The PEB will first determine if you are fit for duty. If fit, the process ends. If they find you unfit, they will rate your unfitting condition (s) IAW the VA's schedule for rating disabilities, as modified by DoDI 1332.39 and AR 635-40.
If they rate you at 20% or less, you will not be retired. You will separated with disability pay calculated at high-three retirement base x 2.5% x years of service up to 12. You will lose all other retirement benefits. You will not receive any VA disability for your unfitting condition until an amount equal to your separation pay minus taxes has been recovered. A rating of 0, 10 or 20% rating will be compensated the same by the military. Because of the VA offset Disability separation is a bad deal all around. In effect you lose your retirement earnings to date.
If they rate you at 30% but the condition is not stable enough for final rating purposes, you will be placed on the Temporary Disability Retirement List (TDRL). You will be reevaluated at least every 18 months up to five years. If on one of those reviews, they rate you at 20% or less, even if the condition is not stable, you will be separated as described above. If at a reevaluation the condition is stable for rating purposes above 30%, you will be permanently retired at that rate. If you go five years and are not stable, they will rate you as if you are based on the level of disability at that time.
While n the TDRL you will receive your high-three retirement base rate X you current rating percentage or 50%, whichever is greater but no more than 75%. When you are permanently retired for disability, you will receive the higher of your disability rating x your high three base, or 2.5% per year of service X high three base. I don't know how your 7 years of reserve duty will factor in. However, if rated 20% or lower, you maybe eligible for Continuation On Active Duty (COAD) until you have enough time for a reserve retirement that will begin paying at the age of 60. Any VA disability will off-set dollar-for-dollar your disability retirement pay unless you have enough years to retire already and your VA total rating is 50% or more. This is known as concurrent receipt and may be modified by law someday in the future to cover disabled retirees under who are not otherwise eligible for a length of service retirement.
While the military only compensates for unfitting conditions, the VA compensates for all service connected conditions. A service connected condition is one that incurs or worsens while on active duty. Make sure all you medical conditions are covered and documented in your final physical to facilitate your VA disability.
If you read through the posts on this board, there is much to be worried about. Education is your best defense. Besides the documents I mentioned above, study DoDD 1332.18 and DoDI 1332.38. A lot is at risk.