i've been hurt before >> reporter: this is shahawn mendes, a 17-year-old singer/songwriter, on his own onstage with just his voice, his guitar, and that smile. this canadian can draw a crowd of thousands in los angeles. you watch me >> reporter: watching him play such wide-eyed hits as "stitches." >> when you're out there and your fans sing it back to you what goes through your heart? >> it's the best. there's no other feeling like having your fans sing your song back to you. it's a good feeling. bring me back to life >> he's really hot, he's really hot. >> i'm sorry it took so long. i'm very sorry. >> reporter: it's the climax to a full day which began hours earlier. >> reporter: on the go, shawn serenading a smaller group, the fortunate ones at his vip preshow. >> i was trying to get my phone to take a picture and i couldn't! >> he looks like an angel came from above. he smiles at you. it's like -- aah! >> reporter: now shawn is due at the teen choice awards across town. >> shawn mendes! >> reporter: at the show he wins a tca for music web star. >> for the fans, i love you guys so mu