You probably have loose valves if you're hearing valve train noise. You probably just need a valve adjustment. A slipped timing belt is a pretty big deal, and it should either always run like shit or not run at all if that happened. You shouldn't drive it at all until it's fixed if you did jump time. It could jump again and hose your motor.

Check your timing marks, but I bet you find the problem under your valve cover. Loose valves will rattle, but they'll still stay tightly closed because of the valve springs. Comprendé?