same post showing different titles

My blog is acting funny. I searched different ways and got the same post url however the title is buggy. Im concerned about duplicate content.

The post url is

http://www.thesafestcandles.com/blog/scentsy-layers-skin-care-products/

when i search in google Did Scentsy Layers personal products add value to our lives? The exact post title I get the correct title

When I search site:www.thesafestcandles.com/blog/scentsy-layers-skin-care-products/ I get a title of Scentsy Layers 7 day Family Challenge Results (which is in fact the name of a previous post “http://www.thesafestcandles.com/blog/scentsy-layers-fragrance-challenge/”

When I searched for Scentsy Products Shawn I came up with the post title 2 down in the google searh results “scentsy-layers-skin-care-products – Scentsy Candles.” This is strange because the title has dashes.

This is really strange. Can anyone look at and enlghten me why this is the way it is and should I be concerned?