Conundrum: When to paint over a painting

Wanting to start a new painting, I was bummed to realize I was short on 24" x 36" stretched canvases. Too impatient to want to go out and buy one, and wishing to save money, I ran across an old painting of the aforementioned size that I wasn't too fond of. The gears in my head (as dusty as they are) began to turn...I could paint over this. Right?

I didn't end up painting over it, and don't know if I ever shall. I don't think there is anything wrong with the act of painting over an older work, and that extends to all mediums. I've drawn over countless old sketchbooks thousands of times, and they aren't any less precious to me than this one particular painting. What is the painting of, since I mentioned that I wasn't too fond of it? It's a self-portrait I painted from looking in a mirror. So many things went wrong with it that I could save that story for a separate post. It is almost as if, because it was such a troubled painting, that I feel some sort of guilt in contemplating the act of covering it up, almost as if to conceal my mistakes.

It's entirely possible I hesitate for a completely different reason. It could be that, despite the problems, I still put in a lot of work into the painting and do not wish to revise that fact. However, it calls into question the power of placing preciousness on any particular object. Why do we do it? Why are some things off limits and others not? I don't know. But I do know the tugging sensation in your chest when something feels wrong. It may be that this is simply the wrong call to make at this point in my life. Perhaps it would feel better, or right, if I was older and more experienced to make that call. 

Could it be that it is simply the first self-portrait I painted from life that makes it special to me? I think that's part of it. The fact that I haven't made that many since also makes me feel the need to keep some sort of evidence that I tried. Some day, once I have painted many more self-portraits, this one might finally join the ranks of the sketchbooks, not too sacred to reclaim its material, but nonetheless well loved.

-Gigi M.