It could possibly be spotting due to implantation which is normal. I had that when my period was due and it went for about 6 days. Home pregnancy tests also turned out faint (because hcg levels still very low at that point). I knew I was pregnant though but Dr sent me for a series of blood tests to check my hcg levels to be sure as well as ultrasound. Vaginal ultrasound showed a sac measuring 2mm but too small to confirm a viable pregnancy.
Only thing to do is to rest and hope for the best while waiting. You can wait another week before testing again. I know even a week feels like forever! But try not to worry too much about it and take things easy. As long as you still feel nausea and vomit, that's a good sign!
Hope it is all good