It doesn't matter if you're good. YET.

Let me tell you my personal philosophy learned through years of just writing for the hell of it and knowing I was no damn good (I now think I am decent).

If you have a passion for something, it doesn't matter if you are good.

YET.

You have to go for it and see what talent you can cultivate. If after whatever amount of time you feel is appropriate you determine you suck (I always wanted to be a rock singer, but though I love to sing, I took a lot of classes and recognized that is a passion I will keep to myself), then you can get practical and decide if you will continue to pour energy into it.

But you first have to give yourself a shot.