Took a pregnancy test today

So I've not been feeling myself, nauseous big time and my sense of smell is driving me potty!! Ran to the bathroom at work so many time today as I thought I was going to be sick. But the test is negative. Now I'm totally confused as to why I'm nauseous but not under the weather!! Only been ttc a couple of weeks though and af isn't due till next week. Any thoughts?? Thank you