2 weeks….TOPS! If you have had a plugged duct do not wait, get in to your OB! If your OB office won’t see you, say this: “I’m concerned I have Inflammatory Breast Cancer.” Seriously! They will get you in within days and if not, go to your family physician or even the ER. It probably isn’t but you shouldn’t fool around. Even mastitis clears up after a few weeks or your whole body gets a fever. IBC stays in your breast or around your breast area and mimics a plugged duct or mastitis.
I didn’t know about inflammatory breast cancer and I waited two months before really pushing the issue.
Here’s what will happen. They will put you on antibiotics. If the antibiotics doesn’t clear you up in a week, they will do a biopsy or ultrasound.
I’m very outspoken about this because everywhere I looked for breastfeeding help avoided saying “breast cancer” so as not to scare breastfeeding moms. But you need to know it is a possibility, albeit rare.
CLERGYGIRL 
I am so glad someone has this out there. I was told I had a clogged duct and they never did any tests. When a second lump grew I went back in and found out in my core biopsy that I had stage 3 breast cancer!! What I was told was a clogged duct was cancer. Never been told it was IBC but think after reading this that was what it was all along. Always insist they do the extra tests it is better to find out you were wrong then to trust your doctor like me and find out they misdiagnosed you. I am only 36 with 3 kids. Women should know about this had if I had I would have forced her to do the tests.