Ovulation test - positive for only one day??

Hi ladies.  I just finished my period (9 days long- post MC :( ) I took an ovulation test day day 11 of my period- negative, day 12-positive in the morning, negative by dinner time. Today is day 13-negative. I got the positive on the digital one(wasn't expecting positive yet so didn't take a regular one that morning, just evening which was negative). My question is..should we get a positive more than one day in a row?! Or at least more than once in a day? Is anyone else using the clear blue digital? I thought it would be the best but idk! I just want my rainbow baby!! Good luck and happy thanksgiving everyone