Opk testing

Stephannie • I`m 22 my husband is 25. I have a precious boy, he has a beautiful angel girl and together we have a handsome little boy. Ttc another wonderful baby for our big family :)
I've been taking opk tests since Sunday and every day since my tests have been positive for a lh surge. I've been following the directions correctly, but I'm just unsure what to think since it's been positive for 5 days now. Has anyone ever had that happen? My husband and I have done the deed everyday hoping to get pregnant. I've also been taking prenatals with dha, could that cause the surge?