Positive opk, Nausea all day??

I’ve had positive strip opks for the last two days today’s being the most positive (test line darker than control line) my question is I’ve been having nausea ALL day and I never get nauseous around ovulation is this normal? What could be the reasons behind it?

The nausea started after sex last night if that matters.. although I don’t think it does ((&& no I’m not asking if it could be anything to do with pregnancy))