Had sex no condom , but he came on the sheets not in me or on me . Was healing from surgery . Had to take an antibotic which gave me an allegric reaction to it which caused nausea , stomache cramps and etc which was way to much stomache acid and still is . Its been about 3 weeks took a pregnancy test and it came out negative . and my period is in 8 days is there by any chance i could be ??????? I'm like nervous