Can't access admin cp

Yesterday I got some errors on the bottom of my page that I discovered, I wanted to fix it and thought there were some plugin causing it. So one by one I deactivated all plugins (I’d about 16 plugins in total and deleted around 6-8 plugins that I didn’t even use).

The error disappeared and I found the plugin that caused it.
However, shortly after I couldn’t access admin controlpanel anymore.

My controlpanel use to be at emilniemi.com/a
But nothing comes up when I go to that, nor emilniemi.com/wp-admin

I’ve one plugin named “better wp security” which I think is the one I set to emilniemi.com/a link for admin cp.
As well I’ve another plugin named “login customizer”.
No idea if I got these plugins activated, I’m not sure I have.

Anyway, I googled about not being able access my login panel or anything. And found a thread about reuploading wp-admin and wp-includes from a fresh install. So that’s what I did now, but still it doesn’t work!!

I don’t care very much about the theme style etc overall, I could fix it back.
But I wish to keep my posts.

I installed everything for pretty long time ago, but I’m sure all my plugins as well the wordpress were up to date. And I had start to frequently use the blog/website for a couple of days ago, so as long I’ve my posts on my MySQL it’s fine, and so far it’s just the FTP files that seems to be the problem.
Though I have very low experience in MySQL and FTP alltogether so if I would delete ALL files I would doubt how to connect the new installation to my existing MySQL and if that would even be working fine.

So if there’s some easy solution right now, if somebody can find a path to my login page, had been great, and wouldn’t have to re-do my website which I’d prefer.

Thanks in advance