shitting=revenge?

Question
Dear Labman
I want to ask what age exactly the dog isnt consider a puppy?
A new problem ocuur that i just realize;As i told u before my lab is a 5 months old female&im a university student,i always go on the weekend leaving my lab for one night on the balcony of my appartement,its wide and large,with toys and food.as i come the next day sometimes in the afternoon:LIKE EVERY TIME i can see that she shit and piss for like 2 days.Actually i take her out for shitting from 2-3 times and pissing 3-4 times per day as she needs!but thats not what i find on the balcony..more than 6 big spots of poopoo!!a friend told me she does that so much for security.and other told me revenge !what do u think of? but i have to,coz i have to go visit my parents once a week and got no one to take care of her!as she & my balcony get dirty,i kept her another day on the balcony cos i couldnt stand this!as i openned the door little bit,she sneak in the appartement and go crazy by chewing and ripping tissues and everything she could find!
The question is ; why she did that?did i hurt her feelings by everytime leave her alone!?or coz i ddnt let her go out for playing!however whenever i have to go out for a night would i leave her news paper so she she wont shit all over the balcony with gigantic size of poopoo?or a tray like cats?which its better and cleaner!would she get used to trays?
sorry again for my lenghy letter: if u see my dog u'll realize she is awkward!but i love her.
thank u so much


Answer
A dog has most of its adult size by 8-9 months.  They are also sexually mature by that time.  It is definitely time to talk to a vet about spaying her.  A dog's personality isn't mature until about 3 years old.  After that time they are less interested in playing with other dogs and do less chewing.  

It is wrong to leave a dog by itself outside over a weekend.  They are social animals and need company.  As she matures, she will become more and more dissatisfied, maybe beginning to annoy the neighbors with barking.  She may jump the railing.  I would certainly expect it if you do not have her spayed and leave her out there when she is in season.  Perhaps you need to take a realistic look at whether you have the resources to keep a dog.  You must make other arrangements for the weekend.  Do you have the $100 to have her spayed?  From one of your other posts, I wonder if you have the time and patience to train a dog.  If you can't find a good home for her, maybe try a rescue.  They take dogs and find good homes for them.  You may
find a rescue near you starting at http://www.akc.org/breeds/rescue.cfm