The Ex on the Beach star ended up sleeping in a different part of the house after security was called to calm her down when she went on a tirade about John, calling him two-faced.
Tiffany got involved when she began to laugh…
Megan was given a formal warning by Big Brother the next morning and told any behaviour of that sort again could result in her being removed from the house.
She apologised and replied: "The only reason I flipped like that at Tiffany is because she flipped at me. I was trying to help Tiffany. I was explaining to everybody how two-faced John is."
Once back in the house, Megan immediately sought out Tiffany and apologised for her behaviour.
Of course, Megan's rant was the topic of conversation at the start of the day. David Gest said: "I don't know how much she drank, but I've never seen that side of her. You couldn't calm her down... that was the heaviest thing I've ever seen."
Meanwhile, John was in the Diary Room giving his thoughts on the night. "I'm just trying to keep a low profile today, I'm just trying to stay out of everybody's way and I'm really trying not to get angry," he said.
"I can't quite believe some of the things that go on in here and the way people manipulate and are just not truthful. It's difficult to know who to trust. Who in their right mind would want to live in this?"
He later commented to a housemate: "It was nothing to do with me. I got stuck in the middle."
Megan happened to over hear that and was quick to tell Stephanie Davis: "Shock, Mr Nice Guy. I was stuck in the middle of it all, no you wasn't, you were bitching. I'm sick of it but whatever; I'm not going to get involved. I've said how I feel, so that's it."
It seems, however, that some housemates may also be feeling that way...
In the Diary Room, Danniella Westbrook backs Megan up by saying: "I understand where she's coming from, I'm the same, she's fiery like me. She's got a point, if that's how she feels and that's how she's been made to feel then she's allowed to say that."
And later that night, Megan, Gemma Collins and Darren Day chatted about John, with Gemma saying to Megan: "You hit the nail on the head with him... he's very controlling."
Tonight, Friday 15th January, at 9pm and 10:30pm on Channel 5
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