I am 13 how long should my penis be? -
When erect it is 5.5 in long when erect and I am pretty tall, is this normal?
You will continue to develop and grow until you are about 19-20 years old. So, you can expect your junk to grow another 2 to 3 inches. You are probably going to be 2 to 3 inches bigger than the average adult male. Your girlfriend will be calling you -Big Boy-.
Average is 5.1 to 6.2 inches. Puberty ends between 16 and 21, unless you are a late bloomer.
http://www.coolnurse.com/penis_size.htm
Go worry about somethin else.