Technically my first race was a Turkey Trot with my sister who I think was training for a marathon. Second race was a Memorial Day 5k this year. I ran it as a training run until I got near the end and I realized there was someone in my age group pushing a double stroller right behind me so I knew I couldn't let him pass me right at the end. That would be embarrassing.
There was also like a five year old girl who had been ahead of me the whole race so I had to keep up my pace once I saw her slow down with like a quarter mile left...couldn't handle that potential embarrassment either lol
And then right at the very end I saw someone in my age group just ahead of me so right when I felt like I couldn't keep up my pace any longer, I was forced to speed up to pass him.
The race was cut short because a business along the route had caught fire that morning so it ended up being pretty much 4k on the nose, maybe 25m short. I finished in 21:35 so I wasn't particularly fast but I was proud of myself for having the will to keep going at the end. Got second in my age group (...excluding the overall event winner...) so I got this really tiny dog tag with a label maker label on it as my trophy. I thought it was really funny and fitting for my middling performance in a small, local "race."
My first race where I'm going to actually try to do well will be a trail run Saturday morning through a mountain bike park going over some of the bike obstacles so it looks like it should be quite fun.