This is a good change that you did to hardening privacy leakage in your app. From a point of an attacker, there is one other way to identify the email is registered in your site or not. But this is depending on how you have implemented your authentication process, performance of your web servers etc..
Normally we store the user password as a hash in the DB along with the salt value(Hope you did the same?). So, if the login process identifies an email is existing in your DB, then it is calculates the hash of given password and try to compare hashes. Calculating the hash of given password takes bit of time. So what attacker can do is, compare the response times from your login page and identify emails which takes longer time to respond.
As a remedy to this kind of an attack. You have to manually control your response time in your login page to a constant.