Clearblue digital OPKs. Help!!!

I got a solid smiley on the clearblue digital dual hormone opk (top) this morning (cd13) after only one day of the flashing smiley. I was a bit confused by it because I thought you had to have at least 2 days of the flashing smiley before a solid smiley. So I went and got last cycle's opk (bottom) and tested with one of the left over sticks from that cycle and u also got the smiley. I used the same fmu for both tests. I'm just a bit worried because Glow predicted my peak fertility day to be Sunday (CD14) while Ovia/FF predicted Tuesday/Thursday (CD16/18). Is this normal? What app(s) should I trust?