Can these really pick up pregnancy?

I never get lines on my opks. Like I have to really look to see something usually so I thought they didn’t work. I’m supposed to be going through a chemical, but haven’t started to bleed yet. Period is pretty late. Hpts faded away to negative about three days ago. I’m all out now so I tried these and was shocked to see lines. Wondering if anyones had this happen and they were still pregnant. Actually going for blood work in a few minutes. Scheduled it before I even took these.