im 16 and had sex with my boyfriend on the 22nd of december my last period was 5th december meaning i ovalated from 26th to 30th december as i have a 38 day cycle and due on 12th jan, but could i be pregnant from precum, he said he didnt cum in me but how can i be sure? i know he didnt urinate that morning but im worried i have a chance of pregnancy... help!