...PT question

So I had took a test on Monday morning after waking up I went straight to the restroom with a test and took this since I was 7 days late on my PMS app and 9 days late on my calendar and it showed a faint line after 7minutes... but became a little darker still leaving one line skittle lighter then another.
 
I looked twice and the first time was just dark but after 3minutes later after brushing my teeth I looked again me saw a fainted line..so I decided to take another test on the next day .
Tuesday morning I woke up at 3-4ish am  And decided to take a test again at the time and it turnt out 
Which became WAY darker then it did... and this time I decided to use a different brand.
I wanted to ask...should I take another one... and how is it possible in a couple of hours well 24hr that the lines became darker...