I have just created a new document and it seem with whatever 'shape' i draw the gradient is on the page rather than the object. The nodes appear to be within the actual shape. Does anyone know what has happened? thanks.

It sounds like you have changed you fill color from the default solid, partially transparent, to a gradient. But before I launch into details for fixing it, could you upload a screen shot for us? I'm not entirely clear what the problem is, so a visual would be really helpful.