Don't be scared, or worried. BwayneF is right. good eye! Now, if your thumb is not too green, and this tree dies, don't stick your thumb in that good eye and give up. You did the right thing saving that tree, couldn't help the timing. Since the timing is off, and the soil is not the greatest, here's my .02 on keeping it alive.
Be observant and attentive rather than scared and worried. It can be ok till spring repot and better soil. Just learn its water usage. Don't listen to anyone (except folks here) about when to water, listen to your tree, and the soil. This will be a battle, but you can win.
Winter is going to be the challenge. Find the most controlled place to overwinter it. Refrigerator, garage, somewhere YOU control watering.
Definitely provide some kind of bottom protection.
Then go get about 5 more, and experiment! Practice practice practice!