KVixen, it totally happens to me. I even get a headache when I eat something sweet tasting, but sugar free!
Actually, though it's frustrating, I think it's a major blessing...it keeps me away from that stuff that actually does make me sick. I know that eating the sugar makes me ill...at the least, it gives me fat, at most, it makes me diabetic, suicidal, asthmatic, have huge, swollen ankles, bad cholesterol, etc.
Yup we're lucky. It sucks at the time, but how great it is to get an instant reminder of what will happen later if we keep eating that stuff?
Feeling your pain, Kvixen.