Xena_ruchika
Google+ and email login are totally different. You'll get two different accounts if you do that. Using Facebook and Twitter login aswell will generate different accounts.
If you created your account using email (gmail) and a generated password, you'll use the email login.
If you created your account using google+, you need to stick to that.
If you initially used G+ login and would like to access the SAME account with your email, you'll need to
1. Click on "forgot password" in the email login option
2. Type in your email
3. Change your password
4. Access your account with the validation code you receive.
This way, you can access the SAME account with email login and G+ login.
Unfortunately, you now have two accounts.