Hi i have a cold the past week&a cough .but when i cough i get dizzy , it's a v hard cough'& my head hurts too. what's causing the dizzyness.thanks?

See below.: During cough pressure in chest rises dramatically and pushes against blood that is trying to flow into the chest cavity and heart from the lower body and head. Cough long and hard enough and flow drops to the point that heart does not have enough blood to push forward. Your brain starves a little for oxygen and sugar - therefore dizzy. A little dehydration can make this much worse.