So me and my boyfriend live together and we used to be very careful about sex, I went off birth control back in november and since then my periods have all been normal and like clockwork, until now. I was supposed to hit my period on monday but it didn't come, I've been feeling sick all week and my boobs are very sore, also I have been getting heartburn though I don't eat spicy foods, and the lower part of my tummy has hardened and just feels weird. Am I going crazy or am I really pregnant? I took two at home tests this week but both were negative...is it too early? Today I started cramping a lil but instead of my period its a brownish discharge? We have sex almost every day and like I said we have started getting pretty careless about protection, I also read somewhere that sperm can stay alive for up to 3 days after intercourse, is this true? Please someone help me!