So I'm getting ready to be a vendor at a flea market. My parents have told me before that I can get rid of these coins they have, and before my dad left he told me to look up the prices for these coins before I sell them so I can get the best deal. It turns out one of the coins was worth $138, so I take all the coins to a coin buyer and I walk away with $237. So I come home and my mom isn't happy. I was planning on selling some of their Star Trek merchandise and she told me that some of the stuff she bought was several hundred dollars, and I'm guessing she paid a lot of money for the coins as well.

What do I do? One, I needed the money more than she did. Second, my dad was the one who gave the okay to sell the coins today. And third, they already told me that it was okay to sell the coins to begin with. I'm sure my mom's upset because she didn't realize how much the coins were worth. But now what? She won't take back the money that I got, and I feel guilty for selling them. What do I do?