Should I be worried about this? Is there something wrong with me?

Hi there,
I m 18 and female. Yesterday i walked into my class and started feeling very nauseous. I got pretty bad anxiety because i was scared i was going to throw up in front of a lot of people so i started to feel very light headed and dizzy and my heart rate went up. Once i left class and got someone to take me home, i felt better for the rest of the night. But this morning, i went to school again feeling fine and then as soon as i sat down in class again i started to feel lightheaded again. I worked myself up convincing myself that there is something wrong with me... what could this be? i am very stressed and get very anxious when i believe theres something wrong with my body... i just started university so the new change is taking it toll on me but i was fine all through september and this just started. should i be worried?