Yep, that was the problem. I removed my address from the hosts.deny file and I can log in again.
Thanks for the second brain, I guess that's all that's needed sometimes
Just in case anyone who encounters the same problem using kloxo/LXAdmin comes along, I will leave this bit of information because the program suggests not to edit the hosts file directly:
Log in to your LXAdmin control panel (usually on port 7777 or 7778, I believe)
Go to servers, select your server (usually localhost on a VPS)
Under LXGuard, click on the connections tab and you should see a table of IPs, their suucessful attempts and how many failed attempts.
Click on the checkbox next to your IP and hit the "whitelist" button near the top of the page. You should now be able to log in.
Hope that helps someone in the future.