My materials seem to be locked on one colour? I've created an object that has a specific (in thie case Glossy) colour, then i have two other objects that are diffuse. I can change the colours using the materials tab or the node trees. However when i render the image the original colors return and the new ones are not there and i have no idea why?

any help?
I think I have an idea what you are referring to. You are duplicating an object and changing the materials of the properties, correct?

When you go to the material of the duplicated it might look like this "Material.002 and then a box that says "2" next to it before the "F""+""x". Click on the number (which is 2) and do so on texture as well if necessary. I hope that helps, as that was my solution.