My kitchen sink stopped working after I turned the valves a little. why?

The kitchen sink didn't seem like any warm water would come out of it so i tried to adjust the valves to see if the warm water is on. I turned them around back and forth several times (I was kind of learning as I go) and i gave up on trying to get the warm water to come on. But now, water just drizzles out slowly. I tried turning the valves in both directions and tested them, I'm sure the valves are open now(they are turned counter-clockwise) and a lot of water still doesnt come out. Like almost to the part where its just dripping.