My boobs have been really tender for the last couple of days. They are so sore I can barely touch them. I am not breastfeeding (My youngest is 2 1/2) and I don't think I'm due on. I've had the Mirena coil for 18 months now and have pretty irregular periods. I've also been pretty emotional and have had some lower back pain - as though I was coming on, last week. Can anyone tell me what they think this might all mean?