Ovulation tests accurate?

Hello all! New poster here, just have a random question... I picked up a clear blue digital ovulation test, and Saturday I had the little smiley face that supposedly meant I was ovulating? However Tuesday night though I ended up getting my period... Do you think the test was a fluke? My cycles haven't been normal since I stopped BC in Feb, can be 1-2 months in-between them... Not sure what to go by here! Any thoughts?