The problem might be with your keyboard. To verify this, connect another keyboard and observe the results. If the problem disappears, it might mean your keyboard is faulty or that its Caps Lock key ...
Some fonts in Microsoft Office are designed to display all letters in uppercase, regardless of whether the Caps Lock is on or off. Copperplate Gothic is one such font. Check this and change the Font.
Are you finding that the Caps Lock function of your keyboard has been reversed, and instead of typing a capital letter when engaged, instead it produces lower case letters? Luckily, this problem can ...