help!!

Went off birth control pill last month after last period (very heavy period). Had to take plan B this Monday due to precaution on friday/saturday. Was suppose to get period on Monday but have not gotten it. Took 1 test last month (negative), one on monday day of plan B (negative) and one tonight (negative). could i be pregnant or a very irregular cycle right now. This test pictures came back with this line VERY quickly