This has been the worst few minutes of Merrin's entire life, and it's likely to keep that position because she is, very soon, not going to have any more life. Ever. Nobody was ever supposed to die, not for real, not forever, not dead as in gone and destroyed and irretrievable, it feels like this is one of the first and most fundamental promises made by Civilization to every child born. And even with hindsight she's not sure any mistakes were made but this doesn't exactly help.
She does all the right things. Probably. There are not very many things anyone can actually do, even Merrin with all of her training, and from almost the start of the emergency it's obvious that none of them are going to matter, but she does them anyway. She tries not to have feelings. Has some feelings anyway, most of them petty, including the fact that it feels very unfair how she won't even get time to finish having her petty feelings.
She doesn't scream, not even after everyone else is screaming and it wouldn't make things worse. She doesn't cry, because what would that accomplish. She tries to hold on tightly to the fact that she had a life and it was a good life and the world is probably better for her having been in it, and that at least won't entirely die with her.
This is not especially reassuring.
It hurts, but not for very long.