What happens after the 14 day (extended or not) trial period?

Do I have to upgrade my account to continue editing my website? I will just be using it as a personal blog to keep track of things. After the trial period will all be lost? I do not plan on upgrading. Thanks!

It won't be lost, you can get access renewed a couple of times at least under trial parameters. But only you can see it until you pay (though visitors can use the captcha)

From your post though it sounds like only you want to see it, in which case you might be better off with a free note taking tool like Onenote.

There are other free blogging tools too which may suit you better. Squarespace is aimed at commercial paying sites in the main that have a high design ethos.

If you create a new account with the developer platform (more complicated things to use if you wanted but still has the same editor as the trail you're on.) your trial will not the end. As far as that, I do not know any more to this.

Once your trial expires your content will be safe for 4 months before it can removed by the system - during that time you will not be able to edit it though.

This is outlined here too

Either of the above options would work for you though - use a completely free service so that you can continue to work on your site without paying, or else use the Developer platform here:

http://developers.squarespace.com/