I need some advice/help getting past my running plateau.?

Have you looked at your foot wear? I had the wrong shoes about four years ago and could only run about 4/5 miles, and suffered with shin splints which sounds similar to what you are describing. A cramp type pain in the shins which becomes more and more intense until you cannot physical run any further. Now I can cruise along for 10 miles, have completed a half marathon 3 weeks ago a cross country one and another this weekend. So check out your trainers, find a running shop which can check your gait and the correct shoes. Hope this helps T