Ive been dizzy for 3 days why?

I'm 13 years old and Ive been dizzy for 3 days straight. I have bronchitis right now (not chronic) and i was taking medicine where 1 of the side effects was dizziness but i havent taken it since 3 days ago at like 9 pm...ive been nauseated too...i dont have a fever...my heart is races at stuff thats not even tiring...its getting really annoyng somebody plz help