My teacher (who is now 62) was telling me of his days in Vietnam and when he told me about this it made me kinda freak out.

He was telling me about how he was promoted from a Staff Sgt to a Sgt Major in one tour because everyone in his platoon was left for dead. He survived a bayonet stab and was shot twice. He then said that he met up with another platoon and in the 3 days of wandering through the forests and losing 3 men to traps, he did not sleep once and starting to hallucinate. Then he mentioned how he imagined a tree right in front of him, hit it, and actually fell over. I can't imagine what he went through during those 6 years doing tours in Vietnam.