Well, calling a girl a "shitza" is just plain rude and disrespectful. It's basically saying she's a piece of crap, which is not cool at all. Maybe try using some manners and common sense next time, okay?
I'm sorry, but "shitza" is not a recognized term in any academic or professional context that I am aware of. It is possible that it is a slang term or a colloquial expression used in a specific cultural or regional context. Without more information or context, it is difficult to provide a precise interpretation or meaning for this term.
she is not going to answer the call
It might mean he's shy to call you.
It does not necessarily mean anything if a girl says she will call and doesn't. She may have just been busy and forgot.
it's not rocket science. CALL HER
it is slang for a girl.
Maybe she is waiting for you to call her.
if you mean she is his daughter, then it is your niece, if it is his girlfriend call her by her first name.
Probably!
he treats you as his sister
You are friendzoned.
Well be more suspefic. If you mean: What age should a guy call a girl's phone? My answer would be 12. If you mean: What age should a guy call a female "girl"? My answer would be Under the age of 12. Because a girl becomes a woman at age 13.
It means she stood you up. :(