What Causes Pain In Breast And Stomach Discomfort?

Hi this whole past week my breast were hurting, they felt full and tender. Now, my stomach feel different like a little bump. Barely started this past week all at once. I have never ever felt this in my life. Not even when I get my period, I never get breast tenderness and they never hurt. My stomach feels different, like a little bump.Why would that be? I took a home pregnancy test this morning, and it came out to Not Pregnant.