It does sounds like your football injury predisposed you to further problems with your shoulder. The Labrum is the socket of the shoulder, and it's hard to dislocate your shoulder without damaging the Labrum in some way (since the Labrum is made up of soft material rather than bone).
However, I still think that your mechanics can affect the likelihood that your will have problems. I have studied the mechanics of large numbers of pitchers with Labrum problems and they seem to share a common mechanical flaw.
Something else you should think of is becoming, if you aren't already, a complete freak about conditioning the muscles of your rotator cuff. That will help to hold your shoulder in the socket.