Hello,
They wont allow you to enter the embassy 15 mins prior to your appointment time. The interview went well. The officer was very nice and asked very few questions. Who is the petitioner, where do they live? Have you been charged with any criminal offences? And have you travelled outside of US and Canada in the past five years? We got 221g because they requested for a document. Other than that he said everything else looks good. Hopefully they issue the visa very soon.