thrown off

''I was thrown off when i saw...'' Can you tell me what does ''thrown off'' mean? I'm sorry i can't give you more context...:-(

Surprised, confused. Discombobulated. As in, "thrown off balance" or "thrown off my train of thought."

"Thrown for a loop" is a more emphatic version the same thing, but I'm not exactly sure where the loop comes in. Maybe the term originated with fighter pilots?

Thank you...i was thinking at these meanings, but i wasn't sure enough.:-)