probably still got some vege growth left, but there's not much you can do to make a short plant change its stripes.
like someone else said, may have limited it with your pot size -- at least if it is a soil grow. a soilless medium can produce large plants with smaller volumes in comparison to soil.
Think hashy is right.. little less light might be good.. and if it bounces back may need to ramp up slightly again, but not as high as before. just watch and react to stretch.