MESSED UP LAYOUT, POSTS & HEADER AFTER MOVING FROM .COM !!!

I moved my site from .com to .org and my whole layout has messed up. There is a cached version here:

https://webcache.googleusercontent.com/search?q=cache:n3sa_CXuqfwJ:lifeisntjustaholiday.com/+&cd=1&hl=en&ct=clnk

Now it looks like this: lifeisntjustaholiday.com

My featured images on all my posts have gone, or have been mixed up with other random images from other posts, I can’t make my header the full 940px anymore it just keeps cropping it to 400px.

PLEASE HELP I’m so close to crying I’m a total .org newbie and seriously regretting my decision to move as it’s clearly just ruined everything.

Thanks so much to anyone who can help!