Advice for a possible IBC turnout

I am 24. About a month or two ago, I went to "pick" at blackheads or pimples on my left boob, and noticed the skin pore was really deep. Felt like rubber(?); It was just weird skin; it itched for a while before I forgot about it. (I think on purpose since I no longer decided to pick there anymore out of worry). About less than a week ago I noticed my skin had become red where the skin was thick and pitting. I broke down and googled the symptoms, terrified at what I found. Inflammatory Breast Cancer?‽ My insurance is state issued Medicaid, so you can imagine the hassle just finding a doctor. After many failed attempts, I finally found an office not an hour away that took my insurance. The woman did a Breast exam but didn't seem very thorough. Didn't look up close and see what I feel she needed to. Even still, she came to the conclusion I should be sent for a diagnostic ultrasound and bi lateral mammogram. The problem with all this is my symptoms point to IBC. My breast was red less than a week ago but now it's almost a purple tint— since then I've noticed a (on left) thickened nipple, slight chest pain on left, dimpled skin right by nipple along with thickened, rubber skin, and it feels hot on the INSIDE. Not the outside. Like a sunburn would.

Today is Sunday morning. My appointment for my ultrasound and mammogram is Tuesday at 2pm. When I made this appointment the woman on the other end of the phone said something towards "I can schedule you for both, but due to your age, they usually don't do a mammogram". I was shocked but persisted with "well, my doctor ordered it..." or something of the sort, and she said "all right no problem, I'm scheduling you for both."

That right there is my biggest fear right now. That they'll doubt me and try me on a couple rounds of antibiotics that I've read about. I've heard that only a biopsy can diagnose IBC, sooo- Can I ask for a biopsy while I'm there for the other two tests? If I tell them how it's worsened? I'm so scared but I'm also anxiety ridden, so it's hard for me to speak up against people who are waaay more intelligent than I am. Do you think the technician would order it if the evidence is there? I'm afraid I'm just going to die in my sleep. I just want this all to be a nightmare.

Edited to mention that my grandma on my dads side had breast cancer, along with my grandpa who had luekimia (spell check?). On my mothers side, my mom died of small cell lung cancer and my grand mother died of oral cancer. It's pretty sickly in this tree. I guess I'm just looking for support, and answers to how to push for a biopsy and how to get one ASAP.