My suggestion? Just go to a hardware store or walmart, something like that.
SOME places have age restrictions, but most don't. Most cashiers really don't care, and they can't ask you what you're doing with it anyways.
It's awkward and scary for like 2 minutes when you're getting it, and then it's over with and it's all good.
But thanks, it means a lot.
AAAND ANOTHER UPDATE.

IT'S UGLY, I KNOW.
It was dark, it was shitty paint, and the wall was rough and dusty. Also, I rushed it and in general was just a lazy mofo.

I wish I had extra paint for a 3d, because this was probably my best one yet. I went painting with an older writer I met for the first time earlier this week (But had talked to over facebook a lot) and he showed me how to cut my lines, do touch ups, etc.
This is the best picture I could get, thanks to the million stupid trees behind me.