Can′t gain access to WordPress because of change in link

Hello everybody, I need your help so much.

I use WP and a theme called Scope from Themezilla. When I was trying to configure my website using WP, I by accident changed the WP-link to my website (nikolajbebe.dk) to the link of a page inside of my website. This has caused that I no longer can gain access to WP and change it back! Basically I′m totally fucked.

So what I did was to delete both WP and the theme for my FTP, and then re-install WP.
That worked fine, but then WP told me, that there already something on my WP-account and I need to change it or deleted. But when I go to https://nikolajbebe.dk/wp-login.php I′m able to log-in BUT NOT able to get access to the WP-administration panel.

What can I do to get access to the WP-administration panel, so that I can change back my mistake??? I can′t go through wordpress.com, I already tried that.

https://www.nikolajbebe.dk (there′s just a blank page here now) but check https://nikolajbebe.dk/wp-login.php

This is so frustrating, please help me if you have any idea.
Thanks, I truely appreciate your help ??
Best, Nikolaj / Denmark