My 18k surprise

As always, I was mostly just trying to re-qualify for Boston (3:40).
After the rain let up I was feeling a bit less cranky and was happy with my pace. We ran along the lake shore which was pretty and the whole route was totally and utterly flat.
I must say that nothing really remarkable was happening and I was feeling good and fueling well. I had no idea where the course was taking me since it had changed so drastically since the last time I ran it.
I like not knowing where the hell I'm going (when I'm racing, at least). It makes the time pass more quickly and everything is new and shiny.
At one point it seemed that I was getting passed a lot, which kind of pissed me off, but I re-confirmed that I was holding a steady pace so it wasn't that I was falling behind. And then a woman said to me, "Way to go! Go get those boys!" and I looked around I realized there wasn't a girl to be seen in front of me and I was running with guys my age and ten years older and so then I didn't feel so bad about getting passed.
For a long time I was going back and forth with this guy and it was becoming irritating, and additionally I just wasn't feeling super comfortable on the course. I can't explain it except to say there was a sporadic sprinkling of runners in front of me and I just wanted someone consistent to follow for a while.
At kilometre 18 I turned a corner and looked over my shoulder and though it was sparse in front of me, there was a huge gaggle of people behind me. I was totally stunned. I wondered: have I been setting the pace for these people for 18k?
Then I got cranky again and vaguely stressed out because of all these people on my ass. No worries as they started to pull past me and, lo and behold, it was the 3:30 pace bunny and his faithful followers. Up until this point I had assumed that the 3:30 bunny was gone and away in front of me.
I mean, how weird is it that just as I was wanting to be a "follower" that a "leader" showed up?
I threw my lot in with them.
At one point we were running in an industrial area and a deer darted out and across the road and tried to get into this area but there was a chain link fence there and it started to panic and tried to find a way around the fence but it couldn't, so it bounded back from whence it came.
It was surreal.