A sick Justin Bieber canceled his concert in Syracuse Sunday night – but hoped to be rested and ready for Tuesday’s show at Madison Square Garden. The scratched performance at the New York State Fair had fans worried about the Garden concert, which was to be filmed for a 3-D movie of Bieber’s “My World Tour.” His spokeswoman, Kristen Foster, vowed that the MSG show will go on.The teen heartthrob was well enough to tweet to his fans from his sickbed. “really dont know what to twitter…im getting rest right now and trying to recover from the not so good news from the doctor…” he wrote. “im gonna be ok just need 2 rest but i wanted all of u 2 know i never want to let any of u down. ever. i really appreciate all the kind words.” Bieber was the picture of health at a New Jersey concert on Saturday, according to David Yi, a Daily News reporter covering the event. “He was energetic, dancing, running around the stage, flirting with his fans,” Yi said. Ticket holders for the canceled State Fair concert will have a second chance to see their idol on Wednesday – or get a refund. (NYDN)