A brown package lands on my door. Inside, I find a plastic vial, a cotton swab and a pointed needle. This is an NHS at-home kit designed to test for sexually transmitted infections. The idea behind the DIY test is to cut down on queues and costs at local centres, and I’m all for it. Until I read the instructions and realise I have to prick my finger with one of three needles, and fill up a small plastic vial with my blood. “Squeeze your finger and milk it,” read the instructions.