Is my breast discomfort from a fibroid cyst or could I be pregnant?

I ovulated on November 13th, had sex that night with my husband and he withdrew. 4 days later, both of my breasts began to feel heavy and tender. On November 20th, I noticed that my left breast was larger than my right breast and also much more tender. I felt around and noticed a mass in my breast.
I went to a nurse practitioner today, and she did a breast exam and said she thought I had a fibroid cyst and that I probably wasn't pregnant. I asked her why then did I have tenderness in both of my breasts, since this is abnormal for me. She said it was just hormones.
I am too early to take a home pregnancy test yet. I'll have to wait about one more week. But does anyone have any insight as to why both my breasts would be tender all of the sudden and why this all just came about this month?

* 1 hour ago
* - 3 days left to answer.

BTW, I believe the nurse when she says I probably have a fibroid cyst. I just don't

The nurse practitioner scheduled me for an ultra-sound on my breast to see what's going on. But I can't get in until the end of the month.

She didn't want to do a blood test b/c she said the labs would be closed for the holidays anyways. I don't know.

You probably have a condition call fibroid cyst disease. And it can cause all the problem you are telling me you have. Your doctor will probably give you a sonogram and a mammogram. To be sure that what it is. And all that is when your fibroid cyst gets big you will have to get them drained. And don't worry this condition does not cause cancer, it is just something us women have to deal with for having breast.

during menstration your beast may feel more tender. you could be pregnant but only the test will tell. And while at the the Doctors office with your visit to the NP why did you not have them give you a blood HCG test to see if you were pregnant. also did you schedule a mamogram to see if you have a cyst.

The timing here sounds a bit suspect. Are you sure your husband withdrew in time? You are just going to have to wait until you get your period or not and then you will know for sure. Oh and most womens breast are slightly different sizes.

in four days you wouldn't have been showing symptoms unless you were already pregnant...... its common for one breast to be larger than the other my left is also larger than my right..... occasionally when the weather changes or when i make changes to my diet/exercise/sleep routine or when i am getting ready to start my breast do what your describing....just i have never found a mass in either breast..... but if you do end up being late..... take a test..