I'm so scared

So I took a pregnancy test this morning and I posted it on Grow. The tested showed a faint line. So I took another test (different Brand) and it was clear as day. Negative. But I still feel weird... stomach cramps and little flutters.... nausea... headaches and etc. But since I saw the negative I just assumed I wasn't pregnant... so I went about my day and took my BC pills and vitamins but now I'm scared. What if I am pregnant and the BC pills I took hurts my baby. I need advice fellow growers. Please respond.