A brutal beating caught on camera shows a house party on Long Island turn violent when a two teens were hurt badly enough they had to be hospitalized. “I had three bleeds in my brain, the doctor said it’s worse than a concussion,” one of the teens said. The 16-year-old boy showed NBC New York his injuries, almost one week after he and a friend were brutally beaten at a house party in Melville. “I had a few fractures in my nose so I had to get no…