Einstein touched on this with his comparison to the hot stove and the pretty girl. Your adrenaline rush could be one of many time-changing chemicals. One article has it as:

Professor Einstein’s secretary was so burdened with inquiries as to the meaning of “relativity” that the professor decided to help her out. He told her to answer these inquiries as follows: “When you sit with a nice girl for two hours you think it’s only a minute, but when you sit on a hot stove for a minute you think it’s two hours. That’s relativity.”

Relativity: A Hot Stove and A Pretty Girl