Light brown spotting & cramps 1 week before cycle. no history of spotting, ever. been on bc pills for 4 years. sexually active. help? preg? something else?

Breakthrough bleed: Sounds like breakthrough bleeding which occurs when you have bleeding at unscheduled times while on the pill. Brown is simply old blood that has been sitting at the back of the vagina. Often things get back to normal the next cycle. If not then schedule a visit to discuss changing brands or changing birth control methods. This is very common. Other than being annoying it is not dangerous.