What is the iOS keyboard doing?

I've been using the iPhone for a number of years now and over time I assume that the keyboard on iOS has learned my little quirks and stuff I type to give the best "auto-correct" suggestion possible should I type something that isn't within the dictionary. Things are a little bit crazy now as I find that it's trying to correct me even when I type regular words, as if it's trying to correct for grammar but last time I checked, it doesn't do that. For example:

Type in "food", auto corrects to "good"

Type in "no", auto corrects to "non"

Typing is now a chore as I have to triple check, even the smallest messages. Just typing these words on their own doesn't have auto correct or suggestion kick in but it would occur in the middle of a sentence. Is there a way to clear the iOS keyboard memory or am I screwed until I get a new phone?