Yes, leave it alone. If you made any bad cuts - left short stubs or torn, rough cuts rather than clean smooth cuts: now would be the time to fix them, rather than later.
No fertilizer, no extra water. The tree now has a bit of an imbalance: a higher than normal ratio of roots to top growth. You are likely to get stronger and faster growth next season because all those extra roots will pump up more than ample water and nutrients. Fertilizing next spring will make it grow even faster - something I sure wouldn't want. This kind of fast growth tends to be uncharacteristic of the normal growth pattern of a tree. Next year you are likely to get very long, unbranched growth. Cutting the tips off a bit won't stop the fast growth, but will make it look more normal because you will be forcing it to branch.
