Amy Winehouse hits the headlines more for her private life – battles against addiction, health and the odd fracas with members of the public — than she does for her music. So it was refreshing to see the media focusing on that aspect of her life again after the 24-year-old appeared at Nelson Mandela’s tribute concert on Friday night and at the Glastonbury music festival on Saturday.

While neither was a disaster, in the opinion of people watching, neither was great either. At the Mandela concert, she showed flashes of her ability and charisma but they were only flashes. Overall she looked lost on stage before the 50,000 crowd, and her voice sounded strained on the higher notes. Tabloid reports picked up on her altering the words to the anthem “Free Nelson Mandela”, which rounded off the tribute to the elder statesman before his 90th birthday. “Free Blakey, my fella”, she sang, referring to her jailed husband Blake Fielder-Civil. To be honest, I couldn’t tell her exact words when watching, but several reporters said they could.

Then she was off to Glastonbury, where 80,000 or so fans generally enjoyed her set, albeit with reservations, including what they described as a slurred, lazy rendition of signiature tune “Rehab”. And again, a scuffle with a member of the crowd midway through the performance and a swear word aimed at U.S. rapper Kanye West dominated coverage.

The question now is “where next?” for Winehouse, who was recently diagnosed with a mild form of lung condition emphysema, and whether her tentative comeback last week heralds a return to the good old days of music-making for the five-time Grammy award-winning star.