I'm sorry to hear about your frustrations, and I definitely want to make sure we can get you back to your email campaigns in your account. Were you receiving any sort of error message when you tried to navigate away from the event you were working on? If so please let us know so we can do some troubleshooting for you.
If you're working on a campaign and want to return to work on a different campaign, or create a new one you can click the "Campaigns" button on the left side of the page.
From there you can click on "Create":
And then you'll get a little pop-up window that allows you to select the campaign type you'd like to work on, which looks like this:
I hope that helps!