Have you wished Justin Bieber a happy 22nd birthday yet? If you haven't noticed from social media, today's the day to do it.If you're a belieber, you've probably already tweeted the singer "Happy birthday!!" 40 times in hopes of him noticing.So far, more than 1.4 million birthday tweets have come the singer's way, according to People . And with his more than 60 million Instagram followers, I can only imagine that number quadrupling throughout the day. Why not join in and let the Biebs know how much he matters to you today?Miley Cyrus did.