This overview shows how many posts (both stories and feed posts) you have made on your Instagram profile where you have used your unique hashtag.
It is a requirement that you always use both your unique links and hashtags when promoting. Do you want to know more about what unique hashtags are? Then read on right here.
On your dashboard, you can only see how your posts have performed on the day you log in. If you are curious to get deeper insights into your content's reach and exposures over a longer period, you should go to "reports" → "instagram."
Read more about your Instagram report here.