Dimple but no lump, armpit and arm swelling... Cancer?

Hi There

I am new to this but really need to hear other people's views on this as I genuinely don't know what to think at this stage. Two weeks ago I went to my GP as I found a dimple on my right breast when I raised my arm. I had also had an intermittent crusty discharge from my nipple for a few weeks. The doctor felt no lumps but did feel a couple of nodules-  he said they could be totally normally however felt he should refer me to the one stop shop clinic which would be 2-3 weeks.

About 5 days later I went to the out of hours GP on a Saturday because I had came out in a rash that was burning. It was like sunburn but was raised. It was just near my armpit. The doctor gave me a prescription for antibiotics. The rash had gone down the next day - before I'd started taking the antibiotics- but the mark of it was still there and my underarm was completely swollen. As the swelling didn't seem to be going down after a few days and I hadn't received any referral letter I thought I'd call my GP and see where I was referred to, only to find out they had forgotten to refer me. The practice manager seemed more concerned with covering this up than trying to help. She told me it had been referred already but when I called the clinic they said she had just put the referral through. She wouldn't get a GP to call me back. I told her about the swelling which she called me back to tell me the GP said unless my breast was red tender or swollen he didn't need to see me.

Anyway, I received my referral letter two weeks after my first GP visit and my appointment date was another 3 weeks away. By this point the swelling was right down my arm. I had a phone consultation with a GP 2 days later who said I had to be seen right away. The GP I saw could not feel any lumps but could see the dimple, the mark where the rash had been and the swelling. She said she would try to rush the appointment on.  She called me later to ask me to go to A&E to have a blood test to rule out thrombosis. Long story short thrombosis and infection has been ruled out which, to me, leaves only lymphedema which I know is linked quite closely with breast cancer. She has managed to get me an earlier referral date that is 9 days away instead of 3 weeks. What I don't understand is she obviously can't think it's an emergency or she would surely have got me in sooner but she has not got any other ideas of what is going on with my armpit and arm. I am stressed out going round and round in my head. One minute I think I must be wasting people's time and this is drama over nothing when there isn't even a lump and the next minute I am convinced I have breast cancer.