Chronology of a COVID-19 infection

I daresay the question asked by most people who become infected with this dreadful virus is – How the heck did I get this? My first signs of infection appeared on St Patrick's Day (17 March, now forever etched in my mind). I traced back the dates, given that the infection is thought to be asymptomatic for 2 to 14 days. During that time, amongst other things which could be considered normal everyday events, I had taken three train journeys, been at a meeting attended by 50 other people, had an eye test, and been out for a meal, any of which, in retrospect, could have put me in contact with an infected surface, a cough or a sneeze, despite the fact that I was washing my hands more frequently than previously. From 17 March, my symptoms continued – diarrhoea (a presenting symptom in a third of cases) and a high temperature – for five days, by which time I phoned the NHS. They phoned back and said that I had a COVID-19 infection and had to self isolate. Five days later, after talking garbage (what's new you all say), the paramedics demonstrated that my oxygen saturation was around 75% (which is a very low level) and I was admitted to hospital.