Am I wrong for asking for it back?

I gave my mom 50$ for a really nice camera. I gave her a payment, to show I was serious about getting it. I ended up getting my uncle's camera so I... Show More

This is not the first time it has occurred. She took my brothers 40 from my aunt this Christmas. Also, I spent about a year collecting change and I got 100 from it, but she took all of it. My dados a terribly stingy man when it comes to money. I just don't know how to feel towards the situation.