Problem moving wordpress on my site

Hi,
I have installed wordpress on my site for years now and it always has been mydomain.com/blog/ but now I decided to just have it appear when someone goes to mydomain.com. Right now it shows on there but when I want to log into it to make a post it still uses the /blog/
How can I change that? So i can just type mydomain.com/wp-admin (or wp-login) instead of /blog/wp-admin (or wp-login) so I can delete the blog map (now my wordpress is on my site twice)

Everything else seems to work fine and if I login to wordpress with the/blog/the post appears on mydomain.com too. But I it would be great if everything just worked fine without the/blog/ part.