EAST RUTHERFORD, N.J. — Derwin James Jr. had plenty of regrets after the Chargers’ loss Sunday to the New York Giants. He wanted to win for himself, of course, but especially for outside linebacker Tuli Tuipulotu and running back Omarion Hampton, who had career-best games. It could have and should have been a game-changing performance in the mind of James, who would know about such things. With likely Hall of Fame pass rusher Khalil Mack sidelined for the second of a minimum of four games because of an elbow injury, Tuipulotu stepped up. “I wish we had gotten the win because he would have been the player of the week, bro,” James said.