Need thoughts

So. My fiancé and I have unprotected sex all the time. The past 6 or 7 times straight he's come inside me. Took a test a exactly 6 days before my period was supposed to start. It came out negative. But I was supposed to start today and haven't. I want to take a test to see if I am but I've been pretty bloated the past two weeks and have been really tired lately. And back aches and small pains in my left ovary. Could the test I took maybe have been wrong?