Printer suddenly printing darker?

[owls]

Sorry to post again but nothing seems to be going right today! I printed a couple of greetings cards which were okay but I felt like the colours and quality could of been a little better as the images looked a bit speckled and grainy. I had a play with the settings and now its printing things a lot darker! I set the settings back to default and I can't put it back to how it was * does anyone know what I may of done wrong? It's a canon TS5350 .. I don't know when printing what to have the settings on as it has standard/photo/cardstock/card etc etc