Constipated, so i ate fiber foods lastnight. woke up with pain in stomach but i couldnt go. shortened breath, hot and almost fainted, very nauseous..?

It's the Fiber!: Since you are constipated, the fiber you ate is absorbing water, the bowel is swelling, and you are nauseous and sweating- that is a normal reaction! Try relieving the obstruction from below by either using a suppository, or giving yourself a (i.e.: Fleet's) enema. Once the constipation is relieved, you can resume dietary fiber without the side effects you're experiencing. Drink plenty of water.