Faint Positive?

AF was supposed to arrive 1/27. Still no signs, not even the usual pre-AF spotting, just extremely tender boobs and light cramps. Tested this morning, what do y'all think? How soon until I can get a "no doubt about it" clear as day line?

I had a Clear Blue say positive last month but a negative the next day, then AF still came around so I'm cautious about believing right now.