I wouldn't worry about this, and I use all caps when I want to emphasize too. But you can also put the world in bold type or italics if you want to emphasize it and don't want to seem as if you're yelling. People misinterpret email messages all the time. I caused a family ruckus that lasted five years once because I said something tongue in cheek, and the other person, being sensitive (which I knew), thought I meant it. No amount of explaining would do. Sigh. You can't do anything about the reactions of others. You can only know your own motivation. If someone misunderstands, you can explain yourself, but that's all you can do. Put it behind you and move on.