1. As far as I know, I am not allergic to any foods. (You are allergic to chocolate, cherries, and coffee?! That must be... horrible!! I feel bad for you...) I have plenty of environmental allergies though... grass/trees, (especially freshly cut grass) dust, pollen, ragweed, molds, and cats. (I used to be very allergic to cats, but now I am just a little allergic to them.)
As for medicines, I am allergic to Septra(sp? it's an antibiotic, I took it when I was little, and I looked like a dalmatian with red spots shortly after) and Prednizone (steroid, I was supposed to take it for pneumonia once, and it made me sooooo sick, it was horrible.)
2. Meh, nothing life threatening, but definitely annoying. Sinus infections, headaches, dizziness/lightheadedness, nausea are my most common symptoms.
3. Not as far as I know!! My dad has some serious allergy issues with most types of berries.