How to delete a Microfeed post

I'm trying to delete a Newsfeed post from a site (the default one that is created when you create a Team Site) but when I click the 3 dots, a delete option doesn't appear, even though I'm a site owner and it was one of my own posts. I tried going into Site Contents > Microfeed, finding the post, opening it, and clicking the Delete icon in the ribbon, but that doesn't work either (it says I don't have access to the page). 

Any help would be greatly appreciated!

Thanks - Pete