LH Surge

Why would an LH surge stay practically positive?! I got a very light line positive a week ago (CD14) and wasn’t sure if that was really it since it was so light. Since then, even up until tonight (CD21), they’ve been one shade from positive or the same shade- positive. I don’t have PCOS and normally ovulate CD 14- CD16ish... what the heck?! Please tell me someone has had this?! 😩 what did you do?!