If your views, comments, likes, and shares seem to have dropped, it is only because of the way they are displayed in the analytics page. The "weekly" view always displays your numbers for the last 7 days from when you are checking it. Therefore, a post that falls outside of the previous week will not be displayed. Because the weekly view of time changes each a day, a post that was included may not be included today. If this was a popular post, this can lead to the appearance that your numbers have dropped.