Possible rape baby

Okay ladies obviously not looking for medical advice, but some advice would be greatly appreciated. Long story short: unfortunately was raped on December 8th of last year. My husband and I were trying for a baby at the time. It was the last day of my period when it happened and I was wondering if it could have resulted in pregnancy. I have a 31 day cycle and I had an expected period on the 3rd of January that never came. Im excited to be pregnant but it's now overshadowed by fear that it is not my husband's. According to eve my fertile days were the 15th of December to the 21st. Do any of you think it could be possible this isn't my husband's baby?