Need advice!

So, I'm extremely confused. About 2 weeks ago I had random brown spotting only wiped twice and it was brown spotting. Nothing else since then. My period was due today, nothing. Took a test this morning and it was negative. My boobs are EXTREMELY sore, my face is not breaking out which is always does right before my period, I haven't been cramping like I always do the day my period starts, and I have been getting very sick to my stomach over certain smells & food. I feel pregnant... But the tests says otherwise. Any advice on what might be going on??