Adjustment of Status - I-485

I did my interview Friday October 14th. It went well. Was approved on the spot. The IO was smiling and pleasant when she introduced herself but got very serious when she was asking us questions. She just asked my name, my husband's name, my father's name. How many kids do I have, who were their father. Where did I do my grocery shopping, how many siblings does my husband have.
Then she asked my husband what was my date of birth, how many siblings do I have, which side of the bed did he sleep.
She then asked me all the questions from the I485, then she said she was approving me for the green card and I could apply for my citizenship in three years or two years and seven months (not sure how many months). We told her thanks you and that was it. by the evening my status online changed to case was approved. I thank you all for your advice on this forum and wish everyone all the best. Filing from Boston and my pd date was April 25th.