Was I wrongfully terminated?

I was fired for "Exhausting FMLA rights and [company name]'s leave of absence policy with no clear return to work day". I asked several times about filing for FMLA with my boss and he said "it's not necessary". I called my Dr's office and my employer never automatically put me on FMLA or anything. 1) Should they have put me on FMLA to start a timer of either me returning or me being released? 2) Can my employer go through a doctor, other than mine, to put me on FMLA ? (I have read that an employer can put people on without their knowledge) I was off for a serious injury, not work-related.