However as the pain was worse in the evening & moved around I eventually suspected that it might be RSI & this was confirmed by my second appointment with a doctor on Friday. He has referred to a physio but that'll take a while to happen & I probably won't see someone via this route until after Christmas.
By chance yesterday I got talking to a private physio at a swimming workshop that DD was doing. He gave me some advice & was able to deal with my immediate pain by strapping my arm:
My right arm
He also gives a 50% discount to anyone associated with the swimming club so am currently trying to sort some cash out to get it sorted out properly. I'm absolutely over moon that I don't have arthritis and am looking forward to getting it sorted as it's still really painful