Especially since she doesn't know how it was edited and shown, all kinds of scenarios were probably running through her head of Perez laughing while doing it and talking about it the entire time, etc.

Perez is the Colonel Saunders of BB, he made mincemeat of that lickle chicken hehe

You could see on her face that she was utterly humiliated

It wasn't just the embarrassing impression, but the fact that Perez made her do it and she was completely oblivious. She'll never forgive herself.