Indesit R24 Fridge Freezer - Fridge won't get cold!?

I have an Indesit R24 Fridge Freezer, and the fridge just won't get cold. The freezer is working fine though.

One of the shelves on the door came slightly out of it's fitting the other evening and I think this stopped the door from closing properly - I only noticed in the morning when the floor was wet around the fridge. I put the shelf back on properly, and still wouldn't get cold. I have since taken that shelf out completely and still nothing. The fridge just won't get cold any more, but I can hear it running.

Please help!!