It happens to most if not all of us. Something extremely emotional happens to us and we're just hysterical. Logic doesn't work. You contemplate punching a wall because that will help . . . somehow. Perhaps you just had your big idea stolen at work, your partner is trying to console you but it only hurts you more, and you are screaming, crying, and about to burn your house down. Either way, you are manic and your voice carries that tone. I have been told that all caps and multiple exclamation point is bad style so
"I DON'T KNOW WHAT TO DO!!!"
is pretty much out. So what would best convey that kind of over the edge, spinning your wheels, shrieking kind of hysteric yelling? Would I just explain it after the dialog? For example:
"Honey what's wrong?" asked unassuming husband of wife who was obviously freaking the f- out. "I don't know what to do," said wife in a way matching her frantic pacing of the house tearing her hair out because of reasons previously stated.