HELP with fonts

PSE15 has suddenly changing all text that I type to UPPER CASE. It worked when I first got it, now it is changing the font. I can't find out why and where to fix this. I have already  reinstalled the program and it worked for a little bit, but now it is doing it again. I have rebooted my computer several times b ut this problem persists. There must be a setting somewhere that I can't find easily to fix this. This occurs with every font in my library. But not in Word or other applications. Where ???????