How about getting a debit card instead of a credit card, linking the debit card to paypal, then buying credits?
You don't need to be eighteen to have a bank account, so whatever pocket money you have, you can slip into your checking account, and spend it with your debit card. You won't be liable for a spending limit until you are eighteen... So you should take advantage of getting a bank account now, while you can.
If you were to, your debit card would come in the mail in about a week or two, and you'd be able to spend away.
And getting a bank account is easy. It literally took me about 40 to 50 minutes.
Want to earn money? It's hard to go out and get a job, I know. But you could go old school, and mow lawns for 20 bucks a piece. Hell, ask your parents if you can mow the lawn for them for a bit of spending money. Then drop that money into your bank account, and you can use it online with your debit card.