Olympic gymnast McKayla Maroney became an internet sensation in 2012 when her I’m-not-impressed expression (even President Barack Obama was charmed, right) became a meme. Four years later, McKayla, now 20, has taken the internet by storm again — but this time it’s because she looks nothing like her former self. It appears the athlete, who retired earlier this year, has traded her coach for a plastic surgeon, Beverly Hills plastic surgeon Dr. Ben Talei tells In Touch. “Her lips have been filled,” he says, adding that there’s also been a change to her face shape. “It’s now heart-shaped, and was likely achieved with under-eye and lateral cheek fillers.” Dr. Talei also thinks McKayla’s brows were elevated with Botox. McKayla denies doing anything to her face, but her fans aren’t doing…