One thing that stood out for me was the little bit of deus ex machina concerning the airlock, in it not having an override available to personnel inside the ship. I've seen this used before, and it jars me as an unthinkably bad design fault. The firehose ploy wouldn't have worked either; in a sensible design, the airlock doors act by default in a mutually exclusive fashion, so that they can't both be open, and the inner hatch would not have sealed on the hose, thus preventing the outer hatch from opening. Finally:
this would not happen; atmospheric pressure acts in all directions, and you've treated it as acting unidirectionally as though it were gravity. Realistically, the pressure would have crushed her to death before she could get out of the hatch anyway--and him, too.She went to grab his arms and was thrown down by a thousand pounds of pressure, the weight of an elephant.
I didn't notice any mechanical errors in the writing (punctuation, spelling, etc.), but the rhythm of the sentences seemed to be a little monotonous overall.
Hope this helps,