Teen Mom 2's Season 4 premiere on Feb. 18 was chock-full of drama for Kailyn Lowry and baby daddy Jo Rivera — and none of it was pretty! We're mostly talking about that nasty bruise on Kailyn's arm following the ex-couple's blowout fight...

So did Kailyn end up pressing charges against Jo after things got physical? You betcha! She filed what's called a "Protection From Abuse" order, preventing him from making direct contact with her and baby Isaac. Kailyn was granted temporary custody of their son until a judge could hear both sides and decide on a new custody arrangement for the toddler.

"I'm not looking to take Isaac away from his dad, those are not my intentions," Kailyn said after the incident.

So what really happened? According to Jo's version of the story, Kail backhanded him and punched him in the face. Jo then shoved her arm down (causing the bruising) in self defense. But from Kailyn's point of view, that's not at all what happened — she maintains that Jo struck her in the arm when the fighting escalated, and never mentions any of Jo's accusations.

We have no idea who'll win this epic game of he-said-she-said, but we do know that Jo plans to fight back. Stay tuned to Season 4 for all the juicy drama between Kailyn and her baby daddy! Whose side are you on?