Dogs hate some folks and love others. Dogs definitely aren't a bunch of Lassies. They're animals and therefore wary and distrustful of other large animals.
Why take care of a dog if you're not experienced at it? Your parents don't know a thing about you, really. I mean, do they think you're Cesar Milan? How long do you have the dog?
If it doesn't get an hour run every day, and taken out 2-3 times a day, you're making trouble for yourself. It's NATURAL behavior for a dog to **** and piss at the borders of its territory. If it's not getting outside much-- then the apartment IS the whole of its territory right now, AND it can only hold it so long- six to eight hours max. So every eight hours you should see this dog take a dump. If you don't, expect it within a few more hours. Once it does its thing, you should be set for another eight hours. That's how it works.
Your parents didn't tell you this?! Do they think you're a dog psychic?