I'm the US citizen petitioner. I don't have any knowledge of how it's handled in India, however everyone goes through the same process of filing the petition and waiting for the NVC to do it's thing. I've learned a great knowledge about the process from this website. If there is a backlog at your embassy then there is not much you can do. That said, you can be proactive in contacting the nvc for case number and completing the necessary DS-160,and trying to schedule the interview and medical.