King was forced to sit out Saturday's opening 3-0 win at Folkestone because of the injury and will miss the games at Dartford and Faversham this week - but the problem is not serious.
"He didn't feature on Saturday as he has a slight groin strain," Stimson said. "It's nothing to worry about and he should be ready for Saturday's match at Welling."
Luke Rooney, Mark McCammon and debutant Chris Palmer scored the goals as the Ryman League Division One South side were comfortably beaten on Saturday and Stimson was pleased with the way the game panned out.
"It was a good workout for the boys," he added. "The main thing is not to pick up any injuries and we've achieved that with some reasonably nice football on display."