Preg test and timing

Does it really matter what time of day you take a preg test? I had a sex slip up on August 25 then took plan b 12 hours after. I had like an 11 day period that started a week before the expected period and went through that week too. I’ve taken 2 preg tests. 1 test approx 2 weeks ago and another last week, both were negative. I took the tests around 11:00am but it wasn’t my first urine of the day. Does it matter? Considering this was 7 weeks ago now that the sex slip up happened