Is Birth Control Pills Safe In Breast Feeding Mothers?

I am 25 years old, I have a son that is almost 1 years old. I have been on a birth control pill ( that is safe to take while I continue to breastfeed my son). I have missed a week or so of my bc pill in the month of May. There were a few days in a row that I missed, and then some days just randomly throughout the month. Starting Sunday night I had a really thick, clear, slimy mucous down there. Then Monday morning I woke up and I had spotting of light brown and cramping. Then later on Monday afternoon / evening it turned to a light pink color. It is a very light flow, I really only noticed after go to the bathroom and wipe. I put a panty liner in, but there is not much that gets left on the liner. Then Tuesday I had barely any bleeding / spotting, but a really fishy odor. Now today being Wednesday I have light brown / pink light bleeding going on, with no cramping. I am just wondering what is going on, could I be pregnant ?