Hydrangeas: Help! Have I killed it? (Hydrangea "Alice"), 1 by CapeCodGardener

CapeCodGardener wrote:
I am new, to this forum, to hydrangeas, and to gardening in the NE (previously from Central Coast CA.) Thus I am completely flummoxed by what has happened to my two new "Alice" hydrangeas: they are drooping and looking pretty sad, as you can see in the photo.

Forgive my dumb questions to a forum full of people who know a LOT about hydrangeas.

The back story:
Sept. 28: two bareroot 2-ft. plants received from gardensoyvey.com Looking droopy, but I was told this was typical of Alices when shipped. Soaked the roots for two hours and then planted them both in potting soil in containers until they were acclimatized and I could decide where to plant them in my garden. Kept them outside in a protected spot under my potting bench because rain was predicted.
Sept. 29: both plants have perked up and aren't drooping anymore. I feel happy.
Sept 29--30 overnight: Temps fall to 45 degrees.
Sept. 30: both plants are REALLY droopy. I feel sad.
Oct. 1 (today): See photo: One plant still very droopy; one perking up slightly. I feel confused.

My questions: Why the wilt? It this a disease? Is it because they are newly repotted? Did I kill or maim them because I didn't take them inside that cold night? If they are going to recover, should I be doing anything to help?

The reason I wasn't more prepared for my new babies is because the plants were sent to me by mistake--I'd really ordered Solomon's Seal, but the nursery people said just to keep the plants! So I didn't really pay for them, but I don't want them to die!

Thanks again.
--Emily, zone 7a