First off, congratulations on being at 31 weeks. Make it to 32, and from what my wife's nurse told us, you're in a much better position. My wife and I did have some of the anxiety of "waiting to be hospitalized" during the pregnancy, but it never occurred. Glad to hear that everything is "stabilized" and not getting worse in your wife's case. You're doing everything you can and are aware of what's going on. Can't ask for anything more (except for preeclamspia to go away).
Things will happen when they need to. I know from personal experience as a husband and dad that this is beyond nerve-wracking. The best thing we can do is take it one day at a time. All of your vigilance will be worth it.
P.S. I forgot to pack my wife's bag also. Ladies, don't think less of me, I did get around to it, it's just not in our nature to really plan some of these things. It's not necessarily the "guy's way" to plan these things out as opposed to using "brute force" (e.g., going home six times to get camera, toothbrush, etc. and having it all in one place at one time.)