The problem is that the symbols Apple chose to differentiate between lower case and uppercase letters — meaning whether or not the Shift key is active — don't give any indication as to what you'll actually see when you tap a letter.
The keyboard Apple gave us with iOS 7.1
Since a picture speaks a thousand words, I mocked up what I think would've been a much better design choice for the onscreen keyboard.
The keyboard Apple could've given us
You're welcome, Apple.