im worried that im pregnant and that im not taking care of m

i used to be on birthcontrol pills but ive stopped taking them for like for six months. Now i dont know if im pregnant i still have until the end of the month but im starting to feel funny ive taking pregnancy test and there always negative. Even though im not on birthcontrol of any type, can it be that is still affecting me or that im just not doing what im supposed to do %-)