Marathon Training Day 1 Week 10

I set out to beat my 5 mi PR of 42:58 I set in Week 10 of my Half marathon training back in October. I got off to a good pace and decided to not look at my watch the first mile. I averaged 8:27 the first mile and knew I have to have an average pace faster than 8:36 to beat my best time. In mile 2 I ran thru a swarm of "gnats" and a few landed in my mouth (extra protein). I had to adapt and tilt my head down and try to close my mouth. I have difficulty breathing thru my nose due what I think is a deviated septum. I finished mile 2 in 8:26 and finally felt in the zone where keeping my pace takes effort and attention. I reached my halfway turnaround in 21:07. Staying in the zone I finished mile 3 in 8:24 and reached 5k in 26:10. In mile 4 I wiped my forehead off with the back of my hand because a forgot my sweatband. I noted 6 or so dead gnats on my hand. I had to push harder again in the last 1.75 miles finishing mile 4 in 8:25. I slowed down to an 8:40 pace at the end of the last mile and slowly pushed up to an 8:05 pace until I had 0.1 left and just gave it all I had left finishing in 41:59 shaving 59 second off of my PR. I did my cool down then looked in the mirror of my car and saw I had more dead bugs on my forehead.