'Teen Mom' Amber Portwood — Back in the Slammer

Teen MomAmber Portwood has been thrown back in jail — this after a judge issued a warrant for her arrest today, has learned.

It”s unclear why the judge issued the warrant — whether it”s related to Amber”s most recent alleged probation violations, including a fight Amber got into at a restaurant last month … or a new one entirely.

Amber is currently being booked at Madison County Jail in Indiana — where she”s now expected to spend the holidays.

She”s due to face a judge on January 13.

Story developing …