Should I take an interim gap year?

I'm an English Literature Undergrad and have just completed my second year.
For the following reasons I feel like an interim year between my 2nd and 3rd year would be a good idea:

- I am heavily in debt. I receive the minimum amount from SF and have exhausted my overdraft of £1500. I am not a lavish spender. i rarely go out at the weekends. This debt has come mostly through rent, bills, and coursebooks. A gap year would allow me to work full-time and help me level my account. (There have been days when I can't afford food)

- I have no work experience in my chosen field. I should have looked for an internship for this summer, but I didn't. A year out would leave me plenty of time to do so. Given I study humanities, I'm never going to find a decent job on a degree alone.

- I applied late to do a dissertation. Or rather I missed the one e-mail (among the half dozen sent to me by the university every day) informing me that I needed to apply. A dissertation looks good on a CV and I'm really irritated that I've missed this.

Right now I'm not seeing any cons, besides disappointing my parents. Could someone give me a more balanced view of the gap year, or am I right?

Also I'd love to hear your interim gap year stories, both positive and negative.