Help I can't ask my girlfriend to homecoming because..?

Whenever I get all tensed up, not always nervous, but when I'm anxious, my hiccups ALWAYS come no matter how ridiculous it sounds. I practiced asking her in the best way ever, and then id be fine. And when I had some balloons and her favorite chocolates and wanted to ask her during lunch, i felt so nervous I felt hiccups coming and what if people would laugh at me " Will you go to the homeco-HYUP." That's my biggest fear So that day I gave out balloons to people and shared the chocolates with my girlfriend like a normal day. Homecoming is in 1 week, I don't want to ask her on Facebook so casually , that's way lame ... How do I get rid of this nervousness? I'm sure she'll say yes to her boyfriend anyways.(me)