What Causes Spotting After Coming Off Of Cerazette?

Have been on cerezette for just over 6 years. Came off it just before november as we are trying for another baby. Ha a small spotty bleed on 24.12.13 for a few days. Not had anything since and pregnancy tests are negative. Am I just being impatient? I fell for my first straight away after comin off cilest which I had been on for at least 8 years. I'm just a little worried I have not had a bleed since the last one. Is there anything I should be doing apart from just waiting? Thankyou Rebecca