two days out and not sure what to do

i'm two days away from my first half marathon and i'm trying to figure out what to expect. this is a training race and i'm heading to it with a strict plan so that's making it difficult to predict an outcome. this will be a negative-split race, my heart rates and pace from the first half of the race lower than those from my second. i have to be smart about it because my first 10k have to be a pace that i can maintain without using up too much of my strength. if i go out too hot i'll crash at the end, but i also don't want to go out too slow because i want to get a time that's fairly respectable for someone of my fitness level. and how am i going to feel? will i be crawling across the finish line? will i be able to get negative splits and still feel strong at the end? is this going to be a walk in the park? will i never want to run again? i'm totally out on this one and it's tough for sure.

in terms of finish time, i'm completely in the dark for two reasons. the first is that i have no previous half marathon times to go by; the second is that i have no idea what my pace will be. if i were heading to the race tomorrow to set a benchmark, my goal would be to run less than 1.30. but that's not what tomorrow is about. tomorrow is about sticking to my race plan and finishing strong. above all else, the toughest thing about tomorrow will be putting my ego in the backseat and allowing the slower athletes to whiz by me at the start. but maybe i'll be able to make up for it by passing them all in the last 10k? we'll see. either way sunday is going to be a learning experience and i'll be sure to enjoy it. the weather looks like it's going to be ideal and i'm looking forward to the experience. even if i do end up collapsing at the end.