Uploaded images not showing with WP 3.8.1

Hello, I have set up the site valeriewartelle.co.uk and since upgrading to WP 3.8.1, I can’t see the new images I upload to the library or the pages. I can however see them if I go into edit media. I read a few threads on the WP Support Forum which indicates I may need to do some alteration to the directory, permissions, etc (?!). This however is gobbledygook to me, and if you could suggest possible solutions, thanks to make it very simple so I can follow instructions 🙂 Hope you can help!

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