If you really needed that lens you might have passed up a good opportunity.

But so what? It doesn't really matter. There will always be more lenses.

My own philosophy is that I can only use one at a time, and probably only really need one lens. Maybe two. More than that is simply indulgence. Never lose sight of your goal and what it is you want to achieve with your pictures. If you always keep that in mind, it's amazing how much better decision making becomes.