Fairly new so bear with me. I've written a class that throws an error message for any duplicate emails on Contacts. While writing the test I thought I'd covered everything the original class does however I'm only ending up with 85% code coverage. I'd like to figure out how to get to 100. 

Class (the lines that aren't covered are bolded and underlined):
 

public class Contact_CheckEmail {

    List<Contact> contacts = new List<Contact>();
    
    public Contact_CheckEmail(List<Contact> trigCon){
       contacts = trigCon; 
    }
    

    public void checkEmail(){
    Set<String> emailSet = new Set<String>();
    
    for(Contact c : contacts){
        
        emailSet.add(c.Email);
    
    }
    
    List<Contact> duplicateEmail = [SELECT Email FROM Contact WHERE Email IN: emailSet];
    
    Set<String> duplicateEmailId = new Set<String>();
    
    for(Contact c : duplicateEmail) {
    
        duplicateEmailId.add(c.Email);
    
    }

    for(Contact c: contacts){
        if(duplicateEmailId.contains(c.Email)){
               c.addError('Email already exists.');
        
        }
    
    }
    
}
}

Test Class:

@isTest
public class Test_CheckEmail {
    
    @isTest static void EmailCheckTest(){
        
        Account acc = new Account();
        acc.Name = 'TestAccount';
        insert acc;
        
        List<Contact> contacts = new List<Contact>();
        for( Integer i = 0;i < 1; i++){
            String iString = String.valueof(i);
            Contact myCon = new Contact();
            myCon.LastName = 'iString';
            myCon.AccountId = acc.Id;
            myCon.Email = 'fakeman@fake.com';
            contacts.add(myCon);
        }
        
        try{
        insert contacts;
        }
        catch (Exception e){
            Boolean expectedException = e.getMessage().contains('Email already exists.') ? true : false;
            System.assertEquals(expectedException, true);
        }
        
        List<Contact> contacts2 = new List<Contact>();
        for( Integer i = 0;i < 1; i++){
            String iString = String.valueof(i);
            Contact myCon = new Contact();
            myCon.LastName = 'iString';
            myCon.AccountId = acc.Id;
            myCon.Email = iString + '@fake.com';
            contacts2.add(myCon);
        }
        
        try{
        insert contacts2;
        }
        catch (Exception e){
            Boolean expectedException = e.getMessage().contains('Email already exists.') ? true : false;
            System.assertEquals(expectedException, false);
        }
        
        
        
    }

}