Are the ovulation digital working then?


I'm on cycle day 17 the last two days I have gotten an empty circle on the digital OPK. This morning I had gotten my first flashing smile face! Then I read so many reviews on them and I just want to know if I can trust it. So just now at 3:00 in the afternoon I got this OPK result on the cheap stick.. so can I trust the digital? I'm still going to test with the cheap ones in the afternoon too but when I saw the flashing smile I felt so happy like when you get a positive pregnancy test!!