Lumps are normal. It's the ones that suddenly appear or cause pain that are anything to worry about. And yes, uneven breasts are normal, too, but it's not true that they'll eventually even out in all cases. Sometimes they do, other times, they don't. I have one that's slightly smaller than the other. The soreness in your breasts is probably due to hormones. My periods were 5-7 days and really heavy with clots the entire time.