I Ate A Piece Of Halloween Candy One Of My

I ate a piece of Halloween candy one of my nieces got from someone's house (heath bar) and on contact it tasted funny, sour, and off. Suddenly my tongue swell, itched, burned a little, I got light-headed, heart palpatations, sudden sweats, and flushed. I spit it out asap, so I had minimum amount and rinsed my mouth out, could it be poisoned or laced with some type of drug? My stomach is a bit nauseas.