I've not posted on here before but have been reading all the support and thought I would tell you my experience as it seems similar to yours, apart from your long wait.
I had a mammogram in July and was called back as there was concern. I had another mammogram, ultrasound and biopsy the first week in August where there said they were fairly certain it was cancerous. It was confirmed a week later as Grade 2 invasive cancer 6-7mm, ER+ve, PR +ve and HER2 -ve.
I had a lumpectomy and sentinel node biopsy just over 2 weeks later and then had to wait just over 2 weeks for the results. I then got the good news that the margins were clear and so was the sentinel node (they only took one). I have been told that it was Stage 1A, which is the first part of the first stage. This is different from the Grade, which refers to the way the cancer cells look.
it is looking like I will not be needing any further treatment (no radiotherapy or chemotherapy) apart from taking letrazole for 5 years and having annual mammograms for 10 years, if I am able to take part in a research project called Primetime. Even if I don't get accepted onto the Primetime trial, I can probably have the same plan.
So, I would think that you could be in exactly the same position as me in a few weeks time, so although it is a worrying time, there is a light at the end of the tunnel.