Can I ask for advice on my next step?

_{Hi all -- I have posted up above regarding my issue with trying to figure out my left breast problem, and I seem to have hit a wall.  I'm breastfeeding my 3-month-old little boy.  About 6 weeks ago I experienced extreme nipple soreness.  Two weeks after that I started having stinging pain in my nipple, going up into my breast and finally into my armpit.  My left breast is swollen as well as my armpit, although I've had a few physical exams with nothing of concern found in the armpit.  I was diagnosed over the phone with mastitis, took antibiotics but got no better.  I went to the ER concerned about IBC, given a different antibiotic -- did not get better.  Returned back to my OB/GYN who scheduled me for a diagnostic mammo and ultrasound -- both normal.  No skin thickening detected.  I had a friend of mine who knew an oncological breast surgeon -- she did an exam but did not do a biopsy because she said that she could not find any abnormality to biopsy.  SHe did another ultrasound but once again, it was normal.  I DO have enlarged hair follicles, but I have those on both breasts, and they don't really look as severe as the pictures I see of the peau d'orange.  Her diagnosis was it was a breastfeeding issue.  I went to two lactation consultants.  I was found to have a bleb, but it is not felt that would cause my breast to swell or the entire breast to hurt.  Nothing clear as to what "issue" this is and I've breast fed before, so I know what feels normal for it.  So what would you do?  I feel like SOMETHING is wrong, obviously because of the pain and swelling.  Do I trust the ultrasounds and mammo?  Do I try to get an MRI?  Do most surgeons have to have a specific abnormality for them to perform a biopsy?  I feel like I can't relax -- I want to know if it's cancer or not, so that I can figure out a plan either way.  If it is I need to diagnose is quickly, if it isn't I need to really focus on whatever else is causing the pain.  I'm interested in hearing from people with IBC so that I can understand how you were diagnosed.}