Should I Be Concerned About A Lump Classified As BI-RADS 3, With An Ultrasound Suggesting A Hamartoma ?

Hi, I got a breast ultrasound and mammogram for a lump. After ultrasound, the doctor suggested it looked like a hamartoma, but nothing was seen on the mammogram to confirm. She said it was probably benign but did not explain what it might be, gave it a bi-rads 3 and wants me to follow up in 6 weeks. When I looked up information online, everything seems to say these kinds of masses should be biopsied or remove and are suspicious. Very confused. Ultrasound description: Finding 1: There is an oval parallel mass with indistinct margins seen in the left breast. Internal echotexture is heterogeneous. There is internal vascularity. Finding correlates to the reported palpable abnormality in the left breast. MAMMOGRAM TECHNIQUE: The following mammographic views were obtained: left CC spot compression with tomosynthesis and tangential projection magnification. MAMMOGRAM FINDINGS:The breast tissue is extremely dense, which lowers the sensitivity of mammography. Finding 1: There is no radiographic abnormality in the region of the palpable abnormality in the left breast.