No. Itch.io doesn't have "credit". In order to receive the funds you need to transfer it to a service provider, like PayPal. From there you can purchase a Google Play Card or anything else you have.
However, keep in mind there are also fees that are deducted from the donations. Itch.io's share, if you're giving them any, the once-off tax clearance cost ($3) and the payment processing fees. From your first $5 donation you will retain only a few cents, if that much. You would need a few more donations before you can request a pay out.