Problem: I Have Tightening Sensation In My Right Breast. It

Problem: I have tightening sensation in my right breast. It feels like someone is pulling my breast up with a rubber band from my clavicle and shoulder area. I, also, notice that about 5 times a day the left side of my areola is being pulled up with the rubber band. I can see and feel this. It is only temporary and I can watch my areola and nipple go to full relaxed normal and full erect normal. My right breast doesn't feel like it fits in my bra right and I notice, through feelings, my right breast way more throughout the day than my left.
What I have done: I went to my OBGYN an had a breast exam. She did not feel anything and referred me for an ultrasound. I did that and it was normal. I was told to follow up if it persists, which it did. I followed up, received another breast exam, to no avail. Therefore all she could do was refer me to a breast specialist. I saw her and she reviewed my ultrasound and gave me a very invasive breast exam and was, again, told there was nothing. Mind you, my symptom never would happen at any of the docs offices. I had to show them pictures.
Background: No family history of breast cancer. 29 years old. 125 pounds. Healthy. I do smoke cigarettes, which I hate, and am working on quitting. I drink half my body weight in ounces of water a day minimum. Dont drink. I have giving normal birth to healthy son at 19. I, also, had blood work done and all within normal range, except my nitrogen level was a little low.
Inquiry: I am looking for some direction. I, obviously have these symptoms, but am being told by several doctors that there is nothing wrong. Something is off. Please help.