Giving Shawn your credit cards and checkbook while manic are probably a very good idea. Can you manage cash? I know I have a very hard time handling cash when I am in town or at a store. If it's in my purse, it's fair game. But at least I can't shop on line or on TV with it. But if you CAN handle it, then getting cash and not having access to your checkbook to spend next month's money would probably be a good solution.
Otherwise, you have to go to the bank, talk to an account rep, and ask them to limit or cancel your overdraft amount. I Don't know if it's possible, but it is worth a try.
Meanwhile, try and not beat yourself up over this. It's spring and we all go a little manic in the spring.