So confused about OPKs

So I thought I had a positive opk on Sunday, and everyone else on here that commented said the same thing. Well, I continued to test, and had a negative this morning, but now this this afternoon. This is a positive opk right? So how do I know which one is the “right” one, or when I ovulated? We’ll BD tonight, but is that already too late if I got the positive this afternoon? We haven’t BD the last few days because my husband is having major stress about us flying on Friday, and it wasn’t happening lol.