Worried it may be breast cancer

Hi I am 26 years old and I am due to go to the breast clinic soon but I am worried that I may have inflammatory breast cancer. I don't have a large rash on my breast but I have got a large thickened area on the upper outside quadrant of my left breast, it doesn't feel like a lump as such it feels as though it is a long hard piece when I push down to check, I also have hard lumps across my breast bone. My breast seems to have changed shape and it looks as though it has dimpled. I am also on the depo provera injection and have been for about 7 years now. Do you think that I could have inflammatory breast cancer? I'm quite scared.

Thank you.