I got my lh surge the other day and bd yesterday and used pre-seed?

Why would My lh surge be postive but Im not having any cervical fluid? I only had it for one day on the 19 th of this month? Has this happened to anyone else? Need to know asap and also my bbt thuis morning was 97.3 and then yesterday it was 98.5 why is this but my lh surge is still postive(tested this morning).