So first, I hate waiting, and it seems inhumane for them to tell you all this and then make you wait 2 weeks. I get it.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4644748/
Lobulated means it looks like it has lobes, like the brain has two different lobes. Hypoechoic means it looks dark.
BI-RADS 4 means it is suspicious for cancer, but doesn't definitely look like cancer, and further testing needs to happen - https://www.cancer.org/cancer/breast-cancer/screening-tests-and-early-detection/mammograms/understanding-your-mammogram-report.html
So, nothing is definite. I'm sure it's scary, but really, it's still unknown. Let us know what happens, and if you have any other questions. Hang in there!