What Causes Penis To Grow Downwards?

Hello. I am 16 years old, and have a circumcised penis as from which I was a baby. Now, I don't know if that really has anything to do with this, but anyway, I've noticed my penis has been growing slightly downwards, not straight or upwards as I have seen through the obvious teen "sources". I just wanted to know if this is normal, is it because of how I let my erections grown in my pants? The way I masturbate (on something rigorously pushing downwards to squeeze penis on something)? Etc.