Do not, under any circumstances, simply shrug off the possibility of VA benefits because it was 'just' three months. Go talk to the DAV folks or the Military Order of the Purple Heart (MOPH), and ask them for guidance. They will help you out and do more than point you in the right direction.
Do this NOW!!! Do not delay. They will be your advocate and know the difference between medical discharge, medically retired and medically disabled, etc...
I used the DAV. They are your friends and on your side, the Big navy is not.