I have to agree with Blue Ire; it does sound like you dad is jealous.

As you already stated, you dad said to you he had to work very hard to earn his money. He now is seeing you make, what he thinks is 'Easy Money', and it's making him jealous.

I would ask him why he is jealous of what you're doing, and tell him he should be happy for you, that you're making money at your age by doing something you learned all by yourself.