I think most of us had it at some point. A moment in which we felt sad about our art. It might have been a full developed artblock, or just a small moment of hopelessness, perhaps questioning our artistic career, asking yourself "Why did I actually start doing this?".
Over the years, I've had many moments like that. Most of them triggered by another failed drawing, a total lack of inspiration (while I needed to get creative work done --nothing more annoying than that!), or another harsh critique that was just a bit too much to handle, at that particular moment.
I've had many times that I doubted myself. There have been times when I questioned my creativity in general. Times when I was sad about just another harsh critique, or depressed for being turned down by another group or publisher. Times when I got angry and shouted that I wanted to quit art altogether.
But eventually, I never quit.
The point is... no matter how angry or sad I am, it always takes me a while to calm down and