When I was 16 (Many years ago) I brought home $40 per week. I gave mom $50 per month for rent, $50 per month towards car insurance (her car) . I also had to put gas in the car and paid $15 a month for my own phone line. I also had a lot of chores, babsitting sister, and making dinner every night. I hated it and was so resentful. My younger siblings never paid rent or anything like that.
However, of the 3 of us I am the only one without bankruptcy on my credit and am the only truly selfsufficient one.
15 pounds is nothing.