I'm sometimes get light headed, feeling nauseous and burp a lot, which sometimes cause the vomit tasting thick spit to come out. Have noticeable mild knee pains, light constant headaches, mild backaches, & mild cramping. Also notice blue veins on chest, breast, arms, thighs, & legs (I'm a black women might I add) Had a period that was one day late but only lasted the 4 days compared to the normal 6-7 days. It was also kinda heavy. Could I be pregnant? If not what could this be?