Tension built between the pair after Ulrika accidentally dropped the piece of crockery while dishing up the group's dinner, but found it too hot to clear away immediately. Nadia then made a point of cleaning up the shards while the rest of the group were eating, a decision that pushed the already struggling Gladiators presenter to breaking point.
With Brian by her side, Ulrika clambered into bed straight after dinner and wailed: "It upsets me so much. It's just so rude.
"Nobody ever has a word with her though. Every time she screams, everyone… goes, 'Oh, she's so passionate'. You don't make excuses for people, they have to understand. I hate her thinking she has the power to upset me because she's so not important."
She continued: "I'm afraid I don’t hold with this thing that she's had to fight all her life. A lot of us had to fight battles... I've had four children, I've been through an awful lot myself. I don't really need to be taught about domesticity by someone who leaves crap hanging around the place."
The upset then escalated into a full-blown row when Nadia came into the bedroom to ask Ulrika what had distressed her - and got told that she was the cause of the problem.
"It's not appropriate to leave it there, you should have cleaned it immediately," Nadia yelled, when Ulrika explained how the former winner's cleaning of the plate had upset her. "If I were to break a glass it would be my first instinct to clean it."
When Ulrika hit back that it was bad manners to start cleaning during a mealtime, Nadia spat: "It's actually bad manners for me to clean a bloody kitchen? The bins are full, no-one cleans it and it's bad manners on my part? Do you know what, I will not clear [up] and you can have that role as well."
An exhausted Ulrika then declared Nadia "insane" for continuously "picking" at her when she was upset, but the Portuguese housemate refused to step down.
"Do not start picking faults to justify your own mistake. Admit that one at least," she stated, before storming out of the room.
The aftermath of the blow-up saw both women separate to be comforted by different camps, as Ulrika cried in bed next to Brian, Chantelle and Preston, while Nadia headed to the sofas and launched into an emotional rant with Makosi and Michelle.
She shouted: "I detest this, I'm detesting what this is all about, I'm detesting what I'm becoming, I'm detesting the hypocrisy in here.
"I'm becoming something that I'm not and I'm not happy with that person and I hate it. You can't say anything, you can't stand up for what you believe in.
"[Apparently] I'm a bad-mannered person, I'm a bad person, and I'm starting to believe it because I'm so unhappy. Just because I'm not crying in the corner like a little victim doesn't mean I'm not suffering as well."
Nadia's emotions got the better of her yet again later in the evening, when she stormed off to the bathroom toilet in tears, screaming that she was "hating everything".
As Makosi and Michelle chased after her and attempted to calm her down, the 33-year-old attacked Ulrika further.
"It's insulting for her to get all that money," she screamed. "It infuriates me 'cause she doesn't even want to be here and yet she gets everything.
"Am I getting the wrong message about what Big Brother's all about? It just angers me a little bit, I just don't know what this show is all about anymore."
*BB official website: www.channel4.com/bigbrother