By all accounts Lt. Caleb Campbell is struggling to catch up with the speed of the NFL while also trying to learn a new position in his first NFL training camp. Drafted out of West Point as a safety two years ago, Lions defensive coordinator Gunther Cunningham has moved Campbell to weak side linebacker. Fellow linebacker Zack Follet, who was on the receiving end last year, said Campbell is getting an earful from Cunningham. “I definitely would not wish that on anybody,” Follett told Mlive.com. “Caleb Campbell is in the exact same position as I was last year. He’s a…