You can carry on using your account, the debit limit is set to 60eur.
If you click on "Members Area" on EDCSource (when logged in) it should show your account status with credit or debit owing. Just below that there should be a box that says "Credit Your Account", where normally you could pay fees, but rather than multiple microtransactions where we lose lots of money to Paypal this credit system works better for us as you can pay for several transactions at once.
However as Grant said do not worry about the fees at the moment.