Pup in Heat

Question
I have a 6/7 month old German Shepherd puppy that we found in a dumpster She has started her first heat.  How long does it last?  Is it true that I have to keep her locked in the house because male dogs will be trying to get in my door at her?  Does this mean that she is finish growing?  Sorry for all the questions this is my first dog so I have no idea what I'm doing.

Answer
Tamara,
She will be in heat for about 3 to 4 weeks.   Yes, keep her in.  A male dog can smell a female in heat up to two miles away.  So walk her and keep a stick with you when you do.
No, she is not done growing.  Unless she is a mix, she should grow until 2 years.
good luck
nancy
PS you might want to have her spayed so you don't have to go through this every six months