is this positive? if so why so faint ?

I have a 28 days cycle and My app says I O'd on the 10th. I am two days late but I took a test 2 to 3 days ago and it was negative I saw the line but it disappeared. And I had one more test  and took it whenn I was a day late so I and this is what the outcome was. Again I'm 2 days late today I have cramps they don't necessarily feel the same as period cramps but I have no period. What do you all think ?