I am so sorry to hear that your test was negative. Maybe you are having some weird symptoms b/c of not getting your period?! I know I have had some dizzy spells (although I never fainted!) and feeling sick to my stomach on more than one occasion, but still no positive pregnancy test or af for me. I am now on day 47 and waiting.
Did they check your iron levels, etc........?
Have you had your hormone levels tested? I go in on friday to have mine done and have an ultrasound to check for pcos.
Take a few days to relax, and start to feel better. Clear your mind for a bit and hopefully your body will start to regulate a little better. I know it's so much easier said than done, but this is what i'm going to start doing, since worrying and trying so hard is obviously not working for me!!!!!!!!!
Keep us posted and don't give up!