Is water damage included in the warranty?

1. Sorry, no. Standard warranty doesn't cover accidental events nor liquid damage. Only if you subscribed to AppleCare PLUSprotection plan, you have 2 accidental events covered, with a very low fee.
2. We can't diagnose that kind of issue remotely, but liquid damage could corrode opther internal components. This corrosion can appear after minutes, hours, months after the damage. You need to have your device inspected at an Apple Store or Authorized Service provider, as soon as they re-open.

Regards

Giulio

Liquid damage is not covered by warranty. The phone can more than likely be repaired but you will have to pay for the repair which can be up to 399$.

Water damage can not be repaired and the device must be replaced.