Does your website belong to you? Well, you paid for the domain and the hosting. You have a theme and they’re your products. Why wouldn’t it belong to you? It’s all about copyright. If you hired a website designer, what sort of contract was it? Did it all become yours upon completion? If you purchased a theme as part of the website design, do you own the theme license? Did you create the text and purchase the rights to the images? Not sure? Check out these links.
Copyright: Did you sign a work made for hire contract, or a copyright assignment agreement? If so, there should be a clause that gives you the complete ownership of the site. If not, it belongs to your designer, and you’re only licensed to use this product. If you wrote the text, it’s yours and you can update or change it.
For the images on your site, if a photographer provided it, that image belongs to the photographer and you’re licensed to use it. If it’s something your designer created, it belongs to him/her and you would be violating copyright if you were to take over and update your website. Please see: http://www.passionforbusiness.com/blog/who-owns-your-website/ (and the link to Has Your Designer Disappeared? within it), http://www.nolo.com/legal-encyclopedia/who-owns-website-created-by-contractors.html and https://www.orbitmedia.com/blog/website-terminology/ or search for “who owns a website design,” “who owns website design copyright,” or “who owns website content.”
The above is not meant to be alarmist nor obstructive. We very much want to help you keep your site secure and updated.