Hey guys...
My problem was actually in a faulty module, installed from unverified source. It was one of those Ship to Pay modules, allowing you to assign payment methods to specific carriers.
Once i installed the module, it actually worked, but the CSS and JS was disrupted. When i removed this module, it all went back to normal.
If you are having similar problem, try disabling all overrides/modules in Advanced Parametres > Performance (meaning, switch to Yes).
If your CSS/JS load properly after this, the problem is in some module. If it happened suddenly, recently, then obviously check the latest modules installed.