Could a lump in breast mean that you are pregnant?

No. It can mean either you have a cyst in your breast and can possibly be Breast cancer at the worst case scenario. You need to go see a doctor to find out what the lump means because a lump in your breast isn't good and can get worse. See a doctor immediately.

Also,

If you are worried if you are pregnant wait till the 7th day of your missed period and take a First Response 5 days sooner pregnancy test (most accurate test voted on the news) and if negative call your doctor and take a blood test and take it from there.

Good luck hun and take care of yourself and call a doctor immediately regarding the breast lump!!!