5 negative tests.. but I have all symptoms

I got somewhat of a period on april 15th. But it was brown and only lasted a day. I have had all the symptoms. Nausea, cramps, fatigued, smelling everything. But all my pregnancy tests are negative. I don't know what I should do. Plus I don't see how I could be pregnant when I take BC.. my husband is not thrilled and I don't know what else to do.. abortion is out of the question but the one person who I need to talk to about this, is completely closing me off..