Less than a day after surgeons removed her appendix, Lindsay Lohan was already yelling and running around on her way out of the hospital. She's one heckuva healer.

TMZ has obtained exclusive video of Lohan exiting Century Park Hospital in Los Angeles, clutching a get-well bouquet. Shocked by the waiting paparazzi, Lohan screamed for a man name "Michael," and darted back inside the building. Moments later, a mystery man pulled up in Lohan's black Mercedes, and whisked away the surgically repaired star.

Careful Lindsay... you don't want to pop a stitch!