What is happening with this, and what should I do?

Earlier today about 12 in the afternoon in my lunch class, my friend next to me began eating a only peanut butter sandwich. I began having a little bit of a hard time breathing next class, which passed a bit, then in the period after, my body became very sore like I am sick or something and that is where I am at now. I did not eat any peanut butter at all, and anyways I do not really have allergies to it. I do, but it is very minimal and I can eat it. Any idea what I should do? I called my mom who is a vet (went to med school for years) and she told me to take some medicine which I did. My body is really sore now and I am laying down, resting. My breathing is a bit better, but I am still having a very tiny bit of a hard time with breathing. All I could do was smell the stuff, and I am like this now. Me being the stubborn retard that I am, I didn't go to the nurse at school and bared through until I got home. What could have happened? Could my peanut butter allergy have gotten worse through the years, or was it maybe just a certain type of peanut butter? And what should I do?