Anecdotally, there seems to be more allergies, especially peanuts, and awareness about them now then when you (and even more so, me) were in elementary school.
There are a lot of theories as to why this may be the case, be very critical of what you read. However, for those of us who don't harbour conspiracy theories here are two mainstream websites, the first being the government of Ontario, with some information. It seems allergies are quite common, about one or two people in every hundred.
As many people have mentioned, the best thing to do in these cases is to go see your doctor, preferrably a specialist in the field (an allergist). Diagnosis made when one is young may have changed in adulthood. Go see your doctor!
Sites:
Ontario Govt http://www.healthyontario.com/english/news_details.asp?channel_id=0&text_id=1041 ( "Peanut allergies may not be permanent"
http://www.anaphylaxis.org/index.asp
On a personal note: From my experience with my own children, Dr. Ham-Pong (Department of Pediatrics, University of Ottawa; consultant, Children's Hospital of Eastern Ontario; private practitioner.) here in Ottawa was very good. (Goggle his name for lots of articles and info).