iPF doesn't support standard emoji, just the ones that you can add via the websites editor. At least not the last time I looked.
Dictation takes practice, and a fairly standard accent for whatever language or region you are in. Here are some tips and commands for Dictation:
Dictation Tips and Tricks
You'll probably find these threads useful as well, though some of it's outdated:
Easy pictorial shortcuts & Helpful places. - For People new to the iPad.