Sources 3 & 7 are premanipulated images, and not useable.

Please read http://www.pxleyes.com/guidelines/photoshop/
5.6. 3D Renders or Illustrations as Source:
Using other people's 3D renders or illustrations (even with permission and no matter in which form they are offered) creates a false impression of your artwork. So 3D renders or illustrations can not be used as sources, unless they are entirely created by yourself. Only acceptable non-illustration brushes and clip art may be used, but you need to mention them as a source too. Don't use an image that has been altered by the source owner nor an entire work created by someone else.

Great beginning entry author, your manipulated sources should be easily replaced (Just a little work, but not a big boo boo). Great to see inventive work. Love the eyes! Just pay attention to your sources. Pre manipulated images are frowned upon because it reflects someone elses's work and not yours. You'll get the hang of it, your skill is apparent so no worries and plenty of time in the contest to initiate the fix. GOOD LUCK.

Author, as CMYK46 has said premanipulated images can not be used. Also, please link the sources to the picture and information page where the license can be seen, not the download eg. the first image the cats eye nebula use this URL

https://pixabay.com/en/cat-s-eye-nebula-ngc-6543-cosmos-1098160/

For more information about sources, please read

http://www.pxleyes.com/forum/viewtopic.php?f=5&t=5644

Wow!! Nice

I link the sources to the picture and information page