Watch : Selena Gomez Does a Perfect Reese Impression,Pics

Selena Gomez's new hit single, 'Who Says,' is an anthem meant to amp up your self-esteem, and what could make a teen girl feel better about herself than getting a rave from one of your idols? That's what happened to Selena at an Oscar party last month when she ran into Reese Witherspoon."I about had a heart attack, she's amazing," she told me."So I walked up to her and was a total goober and I