21 year old female really scared and worried. Advice please? Very much appreciated :(?

I am so scared and worried. I have a large lump in my breast that is infected. It is specifically around my areola. The skin on my breast is red and I am very swollen. My breast is red, even on places that the lump isn't located. I went to the Breast Center on Thursday and they told me that I have an infection. I was prescribed antibiotics and started taking them around 6pm on Thursday and have been taking them ever since. I don't feel like the infection is getting any better. I am on my period at the moment so I don't know if the infection is feeling worse because of my period or what but I am not feeling any improvement. I am really worried. I read symptoms for inflammatory breast cancer and I have most of the symptoms but if I did have that, wouldn't the doctors have known? At my visit at the doctors, they also tried to drain out as much as they could with a needle, but could not get much at all. The substance was "like toothpaste" and very thick, from what the doctor told me. I am really worried. I have a followup appointment tomorrow. Please give me advice :( I have no breast cancer history in my family but I am really scared. Why aren't the antibiotics helping??? The doctors would have definitely known if I had breast cancer at my visit and would have told me right? I got an ultrasound on my breast and everything.