Can early pregnancy cause breast lumps?

I currently have a 21 month old and had my first sonogram yesterday for my second baby. I am 7 weeks a long. But for the past 3-4 weeks I noticed a lump in my right boob. I thought it might have been a clogged milk duct because I’ve been weaning my 21 month old. I talked to my doctor about it and she didn’t seem too concerned after examining it but she scheduled me a mammogram anyways just to be safe. Well today in the shower I felt another smaller lump. I’m really trying not to worry but I am panicking a bit. Has anyone had something similar happen to them?