Changed domain and now I can’t login

I host on MediaTemple. I recently tried to change the domain of a wordpress site and failed. I went into to the settings tab and changed the domain to “https://FOURSTATEMEDICINE.COM” (Don’t ask me why I made it all caps. I was too lasy to shut off caps lock) from “http:0003.mymodernweb.com”. I changed the domain name in both places in the settings tab and then used Cyberduck to drag the files form one folder to the other on my MT-GridServer. The website comes up just fine at FOURSTATEMEDICINE.com, but when I try to log-in it keeps redirecting me back to the log-in page as if the password was incorrect. I have even reset my password and I used copy and paste. It just doesn’t work. I can’t figure it out.