anyone have any idea?

So my period was 10 days late. I had a faint positive test, but negative blood test. Well, my period came 10 days late and it's not clotty (normally my periods are very clotty), it's pretty light compared to my other periods and it's lighter color and mixed with a lot of CM. Usually I got through pads like its my job but this time I'm not. What could that mean? Is it not my period? Am I just bleeding? I see my doctor Tuesday! Thanks in advanced!