How true is it that time you wasted enjoying is not wasted time?
For time to be called wasted, that must mean there was a better purpose for it than what it was used for. The question then is, who decides if that's so? I think that's you, and no one else, not ever. You need to decide what will make you happier on the larger scale to answer that. Suppose you are in college, and graduating college will make you happier in the long run. You have an exam tomorrow for which you need to study. You love to play games. It makes you happy. But playing games instead of studying now would be wasting time you could have used for study because you know graduating with good grades is your greater scale happiness. But if you have already studied sufficiently, playing games is not a waste of time, because there is no longer a better use(within your own framework) to which it could be put. It may be your friend thinks you would be better served by reading some great novel or book of philosophy, and thinks your gaming is always a waste of time that could be better spent improving your mind. If that reading will not further your own short or long term goals (and thus happiness), they are wrong. It's wonderful for them, but your gaming is just as fine for you. They have no right to rank it as more worthy of time than what you enjoy. You need to evaluate your use of time within the framework of your own life and goals and how it effects you and those you care about. Other can give another viewpoint which can be helpful, but never mistake it for an objective one. It will be colored by their ideas of what's important.