It's only a couple months old. It's being grown under grow lights because it is now fall and it would not grow well outside. It was doing absolutely fantastic and then one day it started rolling its leaves downward. I am really afraid to overwater because I don't want to cause root rot, but I don't know if it's overwatered or underwater because everything I look at on the Internet is telling me the signs for both are similar.

I am pretty new to growing plants of any kind, but I really wanted to grow a beautiful tree with my kids and plant it in our yard when we get a house in the future. I would feel awful for so many reasons if I kill this little tree. Can somebody please help me understand how to help it and what to look for the future with watering needs?