Overestimation

When you think you're about to get hit harder than you are, usually by a 98 pound gangster who hits like a vegan.

The guy saw it coming and braced for it, then he realized his overestimation of the 98 pound vegan wasn't necessary after getting hit.

Overestimated

Thinking something will be more than what it is, inflating something.

The girl thought she hit him a lot harder than she actually did, and that it left him unsettled, kind of like an old Luke Skywalker. She had overestimated herself, and wanted other people to do the same thing with her.