missed period after unprotected intercourse, test is negative, but my period is late

So me and my boyfriend Been having unprotected sex , he pulls out but my last period was April 9 2015 I was supposed to get my next period may 10 2015 my cycle is 31 days I took a test on Wednesday the 13th which made me about 3 or 4 days late it came out negative now it's 7 days late what should I do ??? I'm also having a lot of white creamy discharge with slight cramping my boobs are sore nd only one day this week I felt nausea