Paloma Faith suffered a "temporary postpartum psychotic outburst" and thought someone had sewn her head onto another body.
The 'Picking Up the Pieces' hitmaker knew people would think she was "crazy" if she voiced what she thought had happened after she gave birth to her and partner Leyman Lahcine's daughter in December 2016 but was still convinced the bizarre swap had taken place.
Paloma - who had an emergency caesarian section after suffering a womb infection and prematurely ruptured waters - told the 'Sweat, Snot & Tears' podcast: "On day three, I had a temporary postpartum psychotic outburst where I believed that they sewn my head onto somebody else's body...
"I really remember that it is was genuinely real feeling.
"I knew that it sounded crazy and I kept saying, 'I know it sounds crazy and I never would have thought anyone would do this, but they have!' "
Paloma - who is pregnant with her second child after six rounds of IVF treatment - noted that previously difficulties with her pregnancy and birth mean she isn't telling people her due date this time round because she's not convinced things will go as planned.
She added: "My last pregnancy went so wrong that even to people who I would trust not to tell anyone, I can't say it.
"I don't believe that my due date is a real thing. I've got PTSD about it. I'm sort of like, some point in the first quarter of next year but potentially before."
The 39-year-old star - who later noted she hasn't been diagnosed with PTSD but does feel "traumatised" and "worried" - described pregnancy as "appalling" and joked she has an "allergy".
She said: "I think pregnancy is appalling! Obviously I wouldn't have done it a second time if I didn't really like the outcome!
"I love the prize after the first 12 months, not at the beginning. [laughs] I really don't like being pregnant. I don't think it suits me, I don't think my body likes it. It feels like I've got an allergy to pregnancy."
And Paloma - who also joked about her "hideous underwear" - admitted she has airbrushed her photos to help her own confidence.
She explained: "It's so undignified. There's a complete absence of dignity. I mean, I'm wearing the most hideous underwear I've ever seen, just because I've lost the will to live.
"And thank God for photoshop, that's all I can say! You know all those people who are like body conscious, 'embrace everything'. I'm like, 'airbrush the hell out of me!' "
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