Did you water it? It's normal for them to stress a little bit and sag, then they'll shoot back up. You can also use liquid's with a rooting hormone, you can find them at garden places labeled for cuttings or transplant shock.
If you were certain to not disturb the newly formed rootball, then I would agree that all it needs is a little water and a couple of days to recover. If you did any damage to the rootball, then it's going to take longer because it has to recover that lost root growth.
go to the garden store and get some superthrive(plant vitamins, transplanter)!!! also play some mozart sounds weird but it actually increases the amount of nutrient intake by the plant by 1/16 to 1/2%!!!