Please, please help. Lady driver with poorly R53 MCS.

Driving home from work tonight and I heard a loud pop - initially I thought it was the exhaust on a passing chav mobile. However, I started to notice that the back-end had a lot more play. Anyway, got home stepped out of the car, took a look and the rear drivers side has dropped - it almost touches my 17" wheel.

Before I get ripped off because I'm a gullable gal, please can you tell me what I should look for, any suggestions on what I will need to fix it - i.e. new springs. I think my MCS has sports suspension (can check I have original buyers spec sheet). If it is springs what should I go for?

Any ideas gratefully appreciated. Thank you.

Sorry, I've searched for ages to try and find pictures but there is a bar thing on the rear suspension (that's about as technical as I get!) which has been known to detach. It could be that but I think you would be able to see it dangling underneath.
hope someone comes along quickly with a sensible response :)

Thanks for your effort S8rah - all ok, think we were having a Friday night blip and i'd managed to park it oddly on my driveway. It had been a very long week :)