Im trying to conceive. i had end of my period and not since but...?

I have had heart burn on and off seems since mothers day I have had lower back pain and my are killing me they hurts so bad I wake up at least 3 times to go bathroom and evert morning I wake up at 3 stay up for about hour! I have been nauseas but not throw up! I have been emotional crying and forgetful. I took test yesterday negative. I'm due to start period on 25! Any thoughts?