First thing go in to your bank and informe them of the prob and in writting. i understand you have to us direct debit with paypal you need to put a stop on it your bank should help you with that. and then if you wish to have a safe way of buying stuff on the net take out what thay call a paypal card.you go in to a post office to top it up with cash its a new idea paypal started in november you only spend whats on the card and if you try to spend cash thats not on the card the transaction dosnt go through untill you put cash on it yourself.go on to there web site you should find it on the front page you apply.
I hope you get it sorted