Front page lay-out changed

Hello,

The lay-out of my front page has changed after I tried to put a code in for google analytics, that did not work. The code is gone, but my site has since changed.
There is way too much space unused in between blocks and also the blocks are bigger and show a lot of empty space. I do not have enough knowledge to try to change this myself
How can I get it back to the original settings. It worked fine for years and now it looks awfull.
I wish I could add some screenshots here to show, but I do not know how.

Anybody any idea what i can do?
Sincerely, Cora