Tell me what in this please

So a friend of mine brought in a brownie at lunch (keep in mind none of us do drugs or alcohol and we’re all 13 or 14) but we all had a little bit and we all texted each other asking if they could see properly or focus or weren’t dizzy. I got dizzy and I couldn’t focus for my last three classes (the three classes after my lunch period) but now we’re all worried what might have been in them. We all admitted they tasted funny but we didn’t think anything of it. If you have any idea what happened please let me know