I just went in for a breast sonogram because my mammogram was difficult to read due to dense breast tissue. A nodule was found on my left breast. Doctor said it is too small to feel by hand but it does come up on the sonogram. He suggested that I either could wait six months and then get another sonogram to see if it has grown or I could get a biopsy. He doubts it's cancer because I'm 38 and have no history of breast cancer in my family. What does this mean and what should I do? Wait the six months or go ahead and get the biopsy?