When you wake up really early the next morning and your heart is pounding because you drank so much Red Bull the night before.

You don't feel sick like a regular hangover (that is, unless you were drinking jager bombs instead of straight Red Bull...)
"WTF? It's 6am and I'm wide awake, and my heart's pounding like I just did cocaine. Ahh, must be a Red Bull hangover."
by ihaveonerightnow October 5, 2007
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