Hello 20 year old person still in collage and living with their parents. I'm a 30 year old person with two kids who pays rent and bills, and is about to purchase a home. I am speaking to you from the point of view as a parent. I'm sure you do love your pets and care for them, but the fact of the matter is, at 15 you were not legally an adult, you were still bound by the house rules of your parents, and you went against them, whether or not you did it with your money. It worked out for you, congratulations.

Now. YOU DO NOT KNOW THE HOME SITUATION OF THE OP, EITHER. DO NOT. DO NOT. Tell an under age minor still living with their parents to "do it anyway" and "that's how you prove you're responsible." Stuff like this is what will happen. On top of that, OP is even younger now than what you were, and not legally able to hold a job with a steady income, which means they HAVE to use their parents money. How long exactly do you think the 'do it anyway' thing would fly in that sort of situation?