Light period and excessively tired

It could just be nothing.

Do you have sore, larger or tender breasts? Are your nipples darker, morning sicknes or any other symptoms that could signal pregnancy?

I had a few friends that still had their period while pregnant for the first few months and their period was just lighter and shorter, with red blood. From memory dark blood is the older blood lining the walls of the uterus, but dont quote me on that.

Achy and tired could mean an infection. If it continues see a doctor.

I started with aches, similar period to what you are describing adn did nothing, a year and a half later everything is worse add a few more symptoms and i am being checked for all sorts of things, cancer included.

That doesnt mean you need to start worrying about cancer. You are more likely to have an infection.

One last thing. Look at your weight. If you are over wieght or under weight it can make your period funny.

Agreed with Lonni...This could just be your period changing..or more than likely it will be stress.. Different amounts of stress affect your period in different ways. If you have been consistent in using contraception then i doubt very much you are pregnant but as ever there is a slight chance. I would, as Lonni pointed out keep an eye out for symptoms of pregnancy but try not to worry yourself too much even though that is easier said than done...because if you are looking hard enough for pregnancy signs then they might just appear in what is known as a phantom pregnancy so beware and good luck...Jenny