Blazing positive OPK - how long ?

Megan

Ok so a little back story I miscarried April 26 at 5 wks and was told I could immediately try again so we did ... May 7-8 I swear I had a positive opk but it was my first ones I took after miscarriage so I wasn’t sure we BD all that week ... fast forward to this week Monday I had a test look like it was trying to be positive so I told me SO to be prepared ... we did not BD since Saturday as it’s his long week to work and we are on two different shifts so we were waiting for a positive opk to ensure we BD .. today I got what was a blazing positive almost like the one from May 7 - my question is this . I test in the morning before work (7am) and as soon as I get home (630pm) last night was negative this morning was positive .. if we don’t BD until like 7pm this evening is that within the window normally ? I just don’t want to miss it just in case this is really my positive OPK ... sorry for the rambling & thanks for your help