I heard Robert Silverberg say once that
Tommy Smith plays jazz sax and says
"Having been so prolific when I was young, I'm still getting cheques from back in 1958. I'm sure glad he worked so hard."
Or, by analogy to a more primal motivation . . . Dan Savage, sex columnist, said,
"Tomorrow you'll wish you had practiced harder today."
"Your awkward/repulsive stage will pass. In the meantime here's what you need to do: Worry less about getting your 15-year-old self laid and start thinking about getting your 18- or 20-year-old self laid. Join a gym and get yourself a body that girls will find irresistible; read so that you'll have something to say to girls (the best way to make girls think you're interesting is to actually be interesting); and get out of the house and do shit--political shit, sporty shit, arty shit--so that you'll meet different kinds of girls in different kinds of settings and become comfortable talking with them."
What can you do today for your future artist self? Organize the studio? Practice blind contour? Stretch some canvases and get those panels gessoed? Update your portfolio photos?