I have a serious problem! Colour calibration I think?

When I take a picture on my D300 it looks great, I import it onto Lightroom / Photoshop it still looks fine. I edit the picture etc etc looks exactly how I want it to, I upload it onto Flickr or Tumblr and it looks dire! Grey, washed out, underexposed, dull etc etc. I really don't know what to do but the images seem to come up fine when uploaded onto Facebook but when I want a website etc i cant use facebook! Please help x