Man gets Covid twice and second hit 'more severe'

I'm very concerned about the risk of catching it twice, as my wife has been do ill with covid once already - which developed into long covid, so have been following stories like this.

That said the distance between his first symptoms and his 1st positive test seem long, which means there could be a false positive. Talking with my wife she said that some in her group have had repeated positive tests for well over a month since first symptoms.

We will start to understand more now, back in March it was very hard (in the UK at least) to get a test if you weren't hospitalised.