I am 17, and for a long time I have been masturbating using the shower head. My only question really is if there is any danger in that?
There's only a problem if you've been trying to insert the shower head. But I'm going to assume that's not what you are doing.
The pressure from a shower stream is not forceful enough to cause any damage to the genitals. Water is harmless. Using shower spray for masturbation is no more harmful than simply cleaning your genitals during a bath. Just make sure to only use water. Soap, bubble baths and body washes can irritate your genitals and urethra and result in urinary tract infections. You'd know if soap got into your urethra: it BURNS! Other than that, if it's just water, then you'll be fine.