OPK positive 3 days late?

So, I have been taking pregnancy tests, they all came back negative. Today I tried an opk LH just to see, it's positive (pic below). I have read online opk can pick up pregnancy as well, sometimes even before a HCG test. Does anyone know of there's any merit to these claims? Have any of you had this happen?

(I have been having a lot of pregnancy symptoms (sore breasts, cramping, dizzy, nausea, hot temp)! My last period was Nov 22. I took an opk Dec 18, and it was positive, so we tried then. Hope this info helps)