Dh is currently security for a supermarket, long queues today, one customer kept coughing, and coughing. Other customers mentioned to DH that they were concerned. Dh went over and said that as they kept coughing they should be at home, customer said don't worry I've Had The Test it's not covid. Dh went to walk away and then asked when they were tested... 24th April! Dh said that he needed to leave and get retested, which is obviously correct but then I thought there has been not guidance on repeat testing, ie you have a temp get tested and it's negative so when you get a cough you think your fine but should really get tested.
Having shared this story with his workmates DH says it's common for people to be certain that they haven't got it because they have been tested in the past.