I can only write from my own experience. However, after hearing how 'A and E is busier than ever' now, I reflected on what has happened to me.
I went to my GP because I had chest pains and shortness of breath. Both these symptoms had been present for a long time. The GP, listened to my chest and said there may be a little infection there. That was it.
I asked if that would explain the chest pain, which had been going on for weeks. The GP said if I had a pain in that part of the chest, then I needed to go straight to A and E. I replied that it had been going on for weeks, so the GP referred me for an X ray at the local hospital. I had the X ray a few days later.
The X ray showed hyperinflated lungs and I am now waiting for a spirometry test, and have no idea how long the waiting list may be.
My husband was told to go the A and E because his blood pressure was high. A few more minutes with the GP would have indicated that he was under a lot of stress and that could account for the high blood pressure.
So, from these experiences, I am tempted to think that due to pressure on GP services, patients may not be given the time for a more thorough consultation with their GP (or the GP they see at the surgery), and a trip to A and E is advised for some cases that really do not require it.
I am not saying this is the case for the OP, but it could explain in part why A and E departments are always full beyond capacity.