This might be silly, but... I'm a light weight, both in how much alcohol I can drink and in my actual body size. But, despite the fact that I can drink two single-size smirnoff ice's (5% alcohol, vodka), and I don't get drunk (just tipsy) I still feel really horrible as I come out of it. I get really hot and nauseous. Hang overs are supposed to happen the next day, not thirty minutes after the drink!!
Also, my arms, shoulders, and sometimes my neck, feel sore when I drink, like almost as if I can feel the alcohol going right through them. Like, ever got those shots of medicine that makes your arm hurt? It's kind of like that.
It doesn't matter what I drink, whether it's vodka, rum, or beer. Same thing, although it does seem to happen faster with vodka than with beer.