Blood test soon I hope

Erica
Well I took the second test this morning and it came back negative. I will be calling tomorrow and seeing how much a blood test will be. I don't understand though...I haven't had my period since April. And I am always tired, lower back hurts, headaches galore, and I am going to the bathroom more than usual. 
​Is it possible that I could be someone who when they take any test it comes back negative?