Well, I don't want to be the big meanie
, but...
You don't ALREADY have a job, but you're buying another dog? You can't support YOURSELF (ie: mom is having to help you pay the rent) but you're buying another dog?!
Speaking as a mom, it would tick me off to be paying your rent while you felt you could "afford" an expensive pet!
My mother-in-law used to do this with my brother-in-law....she paid half of his bills because he was always short on cash.... meanwhile, he could somehow afford to go to "concerts", etc.
Hon, I really don't mean to sound condescending, and I know I do
, but....many of us have lived many years before we could afford our dream dogs. I've wanted a yorkie all my life, and finally got one when I was nearly 40.
You're very young, and just getting out on your own, and learning to support yourself? Is this correct? In that case, I think you should feel lucky to have the dog you have, and focus on taking the best care of him that you can, and just hope that nothing goes wrong with HIM.
Then after you've reached a point of financial stability and are able to pay all your own bills on your own....THEN think about adding another pet to your budget.
Again....sorry to be the voice of practicality
, but I think you have to look at this logically (as it sounds like your mom is!)