Amy Winehouse just checked out of the clinic on Friday for a chest infection, and today she checked right back in!

A source tells People magazine, "She had a chest infection and underwent some tests to make sure nothing else was wrong. She has been told to give up smoking and was initially struggling with that – she was covered in nicotine patches at one point. But she is making an effort."

We’ve never seen a 25-year old with so many mystery illnesses! Well, we hope 80th time in the hospital’s a charm!