Lines not getting darker

Last Wednesday I took two cheap test and they had super faint lines so I took a first response and it was positive and two digitalis both were positive. Saturday I took another digital and it was negative. I’ve taken two more first response and both were faint and then today I went to a clinic and they said the lines were to faint to consider it a positive and called it inconclusive. I’m so confused and stressed. First two pictures are from Wednesday last one is from Saturday.