How do you get the teacher to recognise you're feeling ill?

Basically this morning I felt sooooo sick when we were doing PE playing badminton, because I had eaten some mikado sticks for breakfast. So when my friends were playing I was just sitting out feeling ill. Then my teacher comes round the corner and to avoid getting in trouble for sitting out, I stood up and had a go at playing. Then she asked if I was ok and I was like 'no i feel sick' and then my friends were like 'she ate too much' and then she sort of just walked away. How could I have kept her there so she would of sent me home, as I had to spend the rest of the day off school. I'm not trying to be an attention seeker btw