I  have my  urgent 2 breast referral appointment tomorrow - I found a lump on my breast 4 weeks ago .I had a clear mammogram in January this year and the lump seemed to have appeared from nowhere - it’s tender to touch and my armpit aches too.

Im really nervous about my appointment. What are the chances of it being breast cancer ? Would it have shown in my mammogram which was only 23 weeks ago ? Amy help or advice appreciated x