The star last spoke to her security team six hours before she was found at home in Camden, North London, and medics said she'd been dead for several hours, The Sun reports.
And police sources told the paper there was no evidence of drugs in her apartment.
The paper also reported Winehouse was given the all-clear when her doctor examined her the night before her death.
Another source told The Sun: "The doctor was happy with her condition. When he left on Friday night he had no concerns."
Security guard Andrew Morris found Winehouse's body about 4pm local time, the report said.
Earlier, Sunday tabloids in the UK claimed Winehouse was seen buying drugs from a dealer in Camden just after 10.30pm. It was claimed she bought narcotics including cocaine, ecstasy and ketamine.
But the singer's family labelled the claims "nonsense", The Sun reported.
A post-mortem is being carried out today to reveal the exact cause of death.
Winehouse's heartbroken mother thought her daughter's death was "only a matter of time" when they met just 24 hours before she died.
"She seemed out of it," her mother, Janis, said. "But her passing so suddenly still hasn't hit me."
Winehouse's mother said she instead preferred to cling for comfort to her daughter's own parting words at the end of an enjoyable day they had spent together on Friday.
Meanwhile, in the few hours between her death and the sales being counted, the Mark Ronson-produced LP charted at number 59, the Official Charts Company said.
Singles from the same album - Back to Black and Rehab - were also popular with fans. The two songs originally charted at 81 and 181 respectively.
Overall, sales of Winehouse albums increased 37-fold between Friday and Saturday while singles sales increased 23 times.
Official Charts Company director Martin Talbot said: "Already the popularity of Amy's music with the British public is being demonstrated, with sales of her albums rocketing by 37 times over the past 24 hours, according to Official Charts Company data.
"While Amy has already had an impact on the Official Charts, we would expect an even bigger impact to roll through over the coming days.
Such a demonstration of her popularity is the best tribute the British public can pay to this extraordinary British talent."
Meanwhile, fans have been laying flowers and other tributes including bottles of vodka at an impromptu shrine outside her Camden house.
"Amy you touched our heart and soul - so sorry it's over," said one message. Another simply read: "Amy, you were amazing."
By mid-afternoon several hundred people had gathered opposite Winehouse's £2.5m home. Neighbours said she had only lived there for a matter of months after the house was renovated.
Paramedics were called to the soul star's house in Camden Square yesterday afternoon but she was said to be "beyond help" and pronounced dead at the scene.
Police say it is too early to speculate on a cause but Sky sources believe a suspected overdose could be to blame.
Winehouse had been troubled by drink and drugs problems throughout her career but news of her death has come as a shock to many.
A spokesman for the singer said: "Everyone involved with Amy is shocked and devastated. Our thoughts are with her family and friends."
Her family said in a statement: "Our family has been left bereft by the loss of Amy, a wonderful daughter, sister, niece.
"She leaves a gaping hole in our lives. We are coming together to remember her and we would appreciate some privacy and space at this terrible time."
The Metropolitan police are currently treating her death as unexplained, but inquiries continue into the circumstances.