Going crazy with the layout!

OK, now I don’t know how the heck this is happening but I finally got the site finished – or at least I thought i had. Went out for lunch, came back to find it had changed.

The header had all been messed up (had a pink background). I can’t get it back to the way it was before. Something has changed today. As fast as I’m clearing one problem up something else occurs. Just now the coupon buttons have changed to green, the text has changed on it. I can’t click through to more details for the listings and my three block footer is now only two. I seriously can’t work out what’s going on.

Is this happening to anyone else? I’ve used other themes and not had these types of problems. I know other themes work differently but I can’t fathom why things are changing when I’m not editing them or if I’m doing something wrong.

Any help appreciated.