Why does the iPad mini keyboard do erroneous self-correcting keystrokes?

My iPad Mini keyboard replaces regularly two keystrokes. It changes the lower case with upper case on the two punctuation keys (the ", and !" and " and ?" Keys). I have to correct the inappropriate changes this does to text in emails and other apps as well. For example, when I introduce a comma "," in a sentence to introduce a clause or series of words, it will change the comma into an exclamation point. Similarly, when I use three dots to indicate text deleted or ignored, the dots will be changed to three question marks.

This happens when typing in Apple apps and non-Apple apps. It seems a hardware issue. I never had this with my very first iPad or any of my iPhones. If no one else has reported this going on with their iPad Mini (mine was bought last December so the original model), perhaps it is a defect unique to my iPad Mini.

I have to read over everything typed. In general there is so much "Apple-determined correction" going on with the Apple keyboard. This is the most obvious and erroneous.