Rock and Roll Denver 1/2 Marathon mini Race Report and A New Coach

I am going to make this short and sweet.
I was holding my own until the 9.5 mile mark when I started walking. My quads were on fire and I tried to stretch them out. I walked up much of the hill to get to the 10 mile mark and then the last three miles were a walk/run. Every time I started to run again, my legs would scream at me. Starting around the 10.5 mark I started to feel crappy. I thought to myself "oh no, not again!". (I got very sick after the last half that I did). At the 12.5 mile mark I took an anti nausea pill as I really wasn't feeling very well. When I finished I tried to keep walking, hoping I would start to feel better but it didn't happen. Two trips to the port-a-potty was followed by dry heaving as we were walking to the car. This was not good, especially in the middle of downtown Denver. At one moment I was ready to have Brian call a medic. I ended up sitting next to a wall while Brian got the car and picked me up. I started to feel a bit better (I took the second nausea pill) but when I stood up I immediately felt worse again. I made it home and spent the rest of the day on the couch. I really don't know why this keeps happening to me.  My average heart rate was 147 so I definitely wasn't pushing it to hard. I didn't happen during the Boulder 70.3 when I was on my feet for many more hours and dealing with the heat. I didn't run as much at Boulder but still. I don't know if it is a nutrition issue. I really need to figure this out as I can't go through this every time I do a long race. I have an appt with my GI doc on Tuesday so I will see what he has to say. I did mention it to him once before but he didn't have any answers for me. Ok, enough of that!
In other news, I have hired a coach.  I had someone who was writing a training plan for me but it just wasn't working out and at the end of the summer I was said "adios" to him. It was during this time where I was feeling really burnt out and discouraged. Numerous things inspired me to contact the coach but what is really important is the feeling I had when I spoke with him. When I hung up the phone I was excited again about triathlon and was really happy that I was excited. I think what I thought was burn out was really discouragement about my lack of running improvement and the lack of feedback and interest I was getting from the guy that had been writing my plan. I have been working with the coach since the beginning of this month and it has been great. He contacts me numerous times a week with encouraging words about the training I am doing and both e-mailed and called me todoy to go over the events of yesterday. He asked numerous questions and really seemed to want to help me figure out what was going on. Oh and he also tells me I will  become a better runner. I think I actually believe him :)