Amber Portwood -- New Mug Shot's On the Blink

"Teen Mom" star Amber Portwood's arrest last week wasn't the eye-opening experience we were hoping for -- just take a look at her mug shot, obtained by TMZ.

As we previously reported, Amber was tossed back in the pokey last week in Indiana -- for the gazillionth time -- after bailing on a mandatory drug court appointment.

Amber had told officials she had to miss the appointment because she was on doctor-ordered bed rest following laparoscopic gallbladder surgery -- but her doctor said she was lying ... so they hauled her back to jail.

Amber's still in custody -- and is expected to stay behind bars for a couple more weeks, until a judge decides what to do with her.