She looks a lot like how she looks today so it's not like she went under some huge transformation.
I imagine this is the look Selena makes when she receives back-to-back drunk calls from Justin Bieber in the middle of the night.
She's just trying a little too hard, and instead of coming across as sexy, this look is a bit tacky.
In this paparazzi photo, Selena steps out wearing a long button-up dress that could definitely double as a jacket.