On the pop-up screen that asks how many of whatever item I'm using that I want to use even if I click the 'cancel' button I still use the item anyways and get the "You feel the effects of the Bottle of Water" thing. So just bringing this to your attention. Not too big of a deal since most players don't really have the need not to use an item. But just in case someone clicks on a rare item and doesn't want to use it, they don't have to lose that item.

That's not a bug, you already clicked "use", so you're going to use one regardless, you're simply given the option to use more than one at once.

Alright thanks