Reading results waaaayyyy after 2-3 min...

I took a test in the AM and it was bfn after 3 min. I checked it later on that day to just make sure and i didnt know if it was dye line or if it was a faint line. My first born was 6 tests (5 neg, last one positive, but faint line). The gyno told me i have low hcg anyway and thats why it took so long. I was 2 1/2 months pregnant by the time it was bfp. So anyways, i took another test later that night and the exact same thing happened. I checked the 2nd one in the morning and i saw an indent. Does this mean anything??? I still have the tests and they still have what i am mentioning. Can anyone help?