So worried

I'm 50 years old & received a letter for a routine mammogram 3 weeks ago,  4 days later I woke up with a red mark on my left breast,  I went to the gp who said it was nothing sinister,  just use moisturiser, she did a full examination. I had my mammogram last Wednesday & told the girl about the mark who said she would mark it on the mammogram,  waiting on results now but the mark is getting bigger,  gone from the size of a small fingernail to the size of 50p piece,  no other symptoms,  I'm trying not to panick & all my family friends just say its nothing to worry about but I'm panicking about inflammatory breast cancer,  can anyone offer any advice/reassurance,  thank you