Welcome to the pinky club. :)
Mine does the same thing & always has. As soon as I press down with my first finger, my pinky shoots straight out. Even if I just hold my hand in front of me and press my thumb and first finger together, it still does it.

Basically, it slowed me down on certain things like shredding, which is why I took up tapping to begin with. You just learn to adjust and do things your own way.