Pregnant?

A few days ago, I started feeling nauseous, fatigued, and had tenderness in my breast. I am not on birth control and have not been tracking my period. So I do not know the exact time of my last period. Yesterday, I started to feel light cramping and last night had spotting. So I put in a tampon thinking my heavier flow would begin. I woke up this morning and there was barely anything. So today, I have continued to have a light to no bleeding. This is odd as I typically have a very heavy period the 1st three days accompanied with heavy cramping. I got a little anxious and took a test thinking it could be implantation bleeding as it was brown. The test was negative.

Am I pregnant?