OP you poor thing.
I had a winter with DS last year- for him it was mostly tonsillitis that was just not going away but also bronchiolitis, croup, and eat infections variously. In and out of A&E, GP and out of hours clinic for months, I’d say twice a week.
In the end I couldn’t take anymore and paid to see a private ENT who totally understood, made an immediate referral to an NHS paediatrician who we saw the next day, on the NHS, who did full blood screen.
Outcome: unfortunate run of bad luck, chronic tonsillitis, and a battered immune system. I took two weeks off work at Christmas, we stayed home and I ploughed him with (even more) dark green leafy veg, vitamin c and rest. He also had a break from the nursery plague pit which helped immensely.
Post Christmas it seemed his immune system started to fight back, and although we’ve had some illness, nothing at all like that year. But I was reassured that two v senior consultant doctors had agreed that something was not right, and that if it continued, there were treatment options.
It will be alright lovely, but half the battle is feeling supported by the medical staff. If you can afford a private paediatrician, even just once, I’d go for it. It’s not fair that you need to, buy such is life and the NHS in 2018. 