Selena Gomez left rehab four weeks early.

The 'Come & Get It' hitmaker checked into The Meadows in Arizona last month and spent two weeks having treatment before departing the facility, but it has now been revealed she had been enrolled in the six-week long DAWN programme and staff at the clinic advised her to see out the whole course of treatment.

Selena - who was reportedly being treated for alcohol, marijuana and prescription drug Ambien use - checked out to attend the Sundance Film Festival in Utah to promote her movie 'Rudderless' and told her advisers she would return to the clinic afterwards.

However, according to website TMZ, she then decided she was ''cured'' and had no reason to return.

The 21-year-old star - whose on/off relationship with Justin Bieber is said to have contributed to her problems - felt completing the initial ''survivor's week'' was enough as that is regarded as the hardest part of the programme.

Following her treatment, the brunette beauty - who cancelled a planned tour of Australia this month - is now focused on returning to work and has been reading lots of scripts and attending casting calls in a bid to move forward.

The former Disney star was spotted leaving an audition with a script and a big smile on her face in Studio City, California earlier this week.