[SalesForce] Email not being sent from the apex code

I have a variable which stores the base 64 image in string. I am trying to send that variable in email body using apex code. Below is code snippet:

Public void submitNewForm()
{
    msg='';
    try
    {
        //List<Object> screenImageObject =(List<Object>)JSON.deserializeUntyped(screenImage);
        system.debug('ImageString'+string.valueOf(screenImage));
        system.debug('<img src='+string.valueOf(screenImage)+'/>');
        //insert Evaluation details
        Evaluation__C eval= new Evaluation__c();
        //5004B000001iP6i,5004B000000fqt6,5004B000000fr2S,5004B000000fr2m,5004B000000fr4O,5004B000000fr4s,5004B000000fr78,
        //5004B000000gJ3O,5004B000000gJ3T,5004B000000gJ3Y,5004B000000gJ3d,
        //5004B000000gYYT,5004B000000gYYY,5004B000000gYYd,5004B000000gYYi,5004B000000gYYn
        eval.Case__c='5004B000000gYYn';
        eval.Score__c=0;
        eval.Max_Points__c=0;
        eval.ResultSnapShot__c='<img src='+string.valueOf(screenImage)+'/>';
        insert eval;

        //get Evaluation id 
        String evalId=eval.Id;

        Document doc = new Document(Name='sampleImage');
        doc.Url=string.valueOf(screenImage);
        //mydoc.folderid = UserInfo.getUserId();
        update doc;
        System.debug('@@@@@@@@@@@@@@' + doc);

        //List of all question and answers id's from VF page
        List<Object> allQuesAns =(List<Object>)JSON.deserializeUntyped(questionsAnswersArray);

        //variable to calculate score and max points
        decimal totalScore =0;
        decimal maxPoints =0;

        // loop of all questions
        for (Object quest:allQuesAns)
        {
            Map<String,Object> singleQuesAns=(Map<String, Object>)quest;

            //insert each answer
            Answer__c ans= new Answer__c();
            ans.Question__c=String.valueOf(singleQuesAns.get('ques'));
            ans.Evaluation__c=evalId;
            ans.Answer_Option__c=String.valueOf(singleQuesAns.get('ans'));
            insert ans;

            totalScore=totalScore+decimal.valueOf(String.valueOf(singleQuesAns.get('points')));
            maxPoints=maxPoints+decimal.valueOf(String.valueOf(singleQuesAns.get('maxPoints')));
        }

        //update Score and max points to evaluation
        eval.Score__c=totalScore;
        eval.Max_Points__c=maxPoints;
        update eval;

        sendMail();

        msg= 'success';

    }
    catch(Exception ex)
    {
        msg= ex.getMessage();

    }
    //redirect page to other page
    //PageReference page = ApexPages.currentPage();
    //page.setRedirect(true);
    //return page;
}

Public void sendMail()
{
    // First, reserve email capacity for the current Apex transaction to ensure
// that we won't exceed our daily email limits when sending email after
// the current transaction is committed.
Messaging.reserveSingleEmailCapacity(2);

// Processes and actions involved in the Apex transaction occur next,
// which conclude with sending a single email.

// Now create a new single email message object
// that will send out a single email to the addresses in the To, CC & BCC list.
Messaging.SingleEmailMessage mail = new Messaging.SingleEmailMessage();

// Strings to hold the email addresses to which you are sending the email.
String[] toAddresses = new String[] {'myemail@company.com'}; 
String[] ccAddresses = new String[] {'myemail2@company.com'};


// Assign the addresses for the To and CC lists to the mail object.
mail.setToAddresses(toAddresses);
mail.setCcAddresses(ccAddresses);

// Specify the address used when the recipients reply to the email. 
mail.setReplyTo('myemail@company.com');

// Specify the name used as the display name.
mail.setSenderDisplayName('Company Support');

// Specify the subject line for your email address.
mail.setSubject('New Evaluation Created : ' + Evaluation__c.name);

// Set to True if you want to BCC yourself on the email.
mail.setBccSender(false);

// Optionally append the salesforce.com email signature to the email.
// The email address of the user executing the Apex Code will be used.
mail.setUseSignature(false);

// Specify the text content of the email.
//mail.setPlainTextBody('Your Case: ' + case.Id +' has been created.');

// screenImage is the variable that comes from a different method in the form of string, which I will use in the setHtmlBody method as below:
mail.setHtmlBody('Hello, Below is the image: <img src='+string.valueOf(screenImage)+'/>');

// Send the email you have created.
Messaging.sendEmail(new Messaging.SingleEmailMessage[] { mail });
}

And I'm calling this method sendMail() in different method where it should fire.
I'm doing anything wrong here? Your help would be aprreciate. Thanks.