Hard to breath, light headed, shaking, nausea?

ok for the past three days i have found it hard to breath, it hurts sort of like my lungs are tight and throat. I'm also shaking quite obviously, iv always had a low blood pressure and some times feel faint when standing but now i feel dizzy a lot and i feel sick a lot, specially after sweets but today iv just had gluten free toast due to being coeliac and i can not sleep. any ideas? i eat well, lots of fruit and good and almonds and chi seeds and fluids and vegetables i like to look after my body and exercise as well.