Even though I think you get better answers at Web Applications SE. I can give you some info.
But how about my email data, can I export it?
As per support docs, if your trial period ends, you will get a notification saying that your account is suspended but you can still access the Admin console and all your data is retained, but users won't have access to email, storage, and other services. People outside your domain can still access files that you shared with them.
This will be the same case even if your subscription ends.
Or it will automatically load into an ordinary @gmail.com?
I don't think this happens automagically.