Tumblr posts can't be reblogged. Help!?

When a photo is clicked, it usually comes up to a page showing previous notes/likes/reblogs. However none of the photos I've posted on Tumblr have any sort of link to this page, meaning they can't be reblogged or liked. I've tried numerous methods of fixing this, but there is no page on Tumblr's help section providing information on how to set up the usual click through link.