A rough run

My training for the Madison Marathon has been going well, I've had some fast runs and felt good afterwards. This past week I ran 10 miles on Sunday and felt awesome. I decided to do this today's long run on Thursday since I was on Spring Break. I didn't think I would have enough time since my husband and I were traveling for Easter. I decided to run on Thursday and I knew it was going to be pretty warm (It was 80 and 80 in April in WI is remarkable) so I left around 10ish. I had a route I was doing form my last marathon training program and I was excited to get back on this route. I was going strong, got to my turn around point and was feeling good. No pains or anything. I did have to walk a couple hills though. This was my first run in the warm weather since last year and I think it started getting to me. By the time I reached 11 miles I was out of water and my had a slight headache. I popped into a Papa Murphys to refill water bottles and then shuffled along to mile 13, I was really starting to feel bad at this point, I had my headache and a stomache and I was really tired. I think I just gave out mentally and then decided to walk the last 2 miles. I really started doubting my ability to finish this upcoming marathon and was really disappointed in myself. My husband reassured me though and we went out and got some nutrition and new running gear and some endorolytes. I think I had an off day due to a couple different factors, heat, nutrition, running two long runs so close together and mabe not enough salt in my system. I have high hoped for this Sunday's 16 miles.