Feel sick

All week ive been feeling sick like naseous n stomach aches. I take birth control pills the one called Lo n ive been taking it since 8 weeks post partum i had my baby in april. Ive missed it once after i got my last period which was my first period since having my baby. I havent had a heavy period since then just spotting like 2 weeks ago n today im spotting again but brown n pink blood like last time i was spotting. Has anyone had this happen before. I took a test n the first one came with a faint line n the rest were negative with one digital one. I took stomach medicine but i still feel sick.