Did I rest to early?


So I have long cycles, within the last 12 months my shortest cycle was 28 days and my longest was 44 days, though within the past 6 months they have become more regular, (32-36 days). I'm not on birth control/using protection of any kind, husband and I use the family planning method, and the calender said I was ovulating on July 4th. My body seemed to agree as I was having my normal ovulation cramps and several other symptoms that I get every time I ovulate. We were planning to start ttc on September, and were not opposed to conceiving early (it took 6 months to comcieve our 2nd baby). Anyways, we had unprotected sex on July 4th when I was most likely ovulating. I am now on day 41 of my cycle, no period. Having a few possible symptoms. But I got a negative test. I tested last night, about 16 days past conception. It was just a dollar store test, and it expires in December, if that matters. I am around 4-7 days late now. . . in 12 months I have only been this late twice, and both times I was under severe stress, sick, and not eating (lost 10 pounds in 14 days kind of stress and flu). Got a better pregnancy test, and am going to test in the morning with 1st morning pee. I was SO sure I was pregnant Could my 1st negative test be because I tested to early and at the wrong time of day?