Amber Portwood is under close watch in jail, according to an inside source - her.
A letter the Teen Mom train wreck wrote from inside jail claims that officials even made her use a flexible writing utensil to pen it ... so she won't shiv anyone.
Prisoner-proof pens are standard issue with people viewed as violent threats, but Ambs says people think she's a danger to society and she'll end up in prison.
"I don't think I'll ever take this sh!t for granted," she says. "I'm scared I'm going to prison ... All I think about is Leah and how she needs a ro-model (sic)."
She adds, "I am a good person and I pray that I can change my life."
Amber wrote the letter to her brother last month after she was thrown in an Indiana jail for drug possession and failing to provide a urine test (as per her probation).
She's scheduled to appear in court on Jan. 27 for her probation violation hearing. She faces two years behind bars if convicted, which is not looking like a big stretch.
She's also staring at an eviction hearing in the meantime. Rough.
In the meantime, here's hoping she gets counseling while behind bars and reassesses her life ... while having her belt and shoelaces taken away from her.