I updated my iPhone to iOS 10.0.2 & got an email saying my AppleID was used Was this from the update? Or was I hacked?

The thing is...I checked the current devices logged in and it was only my iphone with the same divide ID and same operating system. It also said the time that my AppleID was used was from my memory around the same time as the update.

So it seems like no one else has hacked into my AppleID.

Is it normal to trigger that kind of alert after doing a normal update?
No, you weren't hacked.

This is perfectly normal depending on the settings of your device at the time of the update.