Need help

Well i have an irrgular period so i dont know when i ovulate. Ive been getting my period on the 11th for 3 months. Me amd my boyfriend had unprotected sex on the 8th he cummed inside 2 times.but it leaked out? Could i be pregnant? I usually get bad cramps i have mild cramps today. & if i was to take plan b to orevent it but took it 2 days late would that still work?