I don’t have a credit card yet but I would like to use Google Wallet to buy stuff – can I use my mobile account to charge my Wallet?
No.Visit the link below for more information -
I don't think it is possible to use your mobile account to buy stuff using Google wallet. As far as I know you can only link credit card or debit card to your Google Wallet.
You can read more about it at Google Walle Faq. Read the first question under Payment section.