Have you actually spoken to your bank yet? Get the general query number from 192 and give them a call - they won’t be mean to you, and they will be able to talk you through what options are available to you. There are often short-term loans available, or they may be able to offer you a buffer zone. Many people find themselves in similar situations and banks are used to dealing and helping with it. Give them a call and you’ll have a clearer, calmer view (make sure they explain to you clearly anything that you might get confused about) and you’ll feel less panicked.
A small note - I am confused as to why you have your credit card up to its limit and yet are unwilling to break into your overdraft - in my experience the interest on overdrafts is less than on a credit card.
Also, for general financial advice, you can get free one-to-one consultations with a debt consultant at your local Citizens Advice Bureau (find their number in the phone book).
As Caricci said - temping is an excellent way of filling the employment gap. Register with a few in your area - again, look in the Yellow Pages. The temp market is slowly picking up again after a fallow few months, so you should be able to find something even if it is just data entry. When you need the cash you gotta do what you gotta do.
Good luck on managing your finances and finding a job soon.