Unwanted stretched text within Span element HTML - html

Question

I am trying to display a message within a span like below
<span class="glyphicon glyphicon-exclamation-sign alert alert-danger" id="ErrorMessage" style="display: none;" aria-hidden="true"></span>`
This span has no text by default but will be populated with error text depending on what error occurs.
The problem is that the text appears stretched within the element and it looks bad. I am not sure what way to approach this. Any advice would be appreciated.
EDIT: The problem only occurs when I add the "glyphicon" class.
I am populating using JS like:
var msg = document.getElementById("ErrorMessage");
msg.innerHTML = "There has been an error";`
I have no custom CSS styles involved here.
<div role="main">
<span id="maincontent"/>
<div class="container">
<div class="jumbotron">
<div style="height: 50px; float: center;">
<h3>List Herd Numbers in Commonage</h3>
</div>
<form role="form" id="HerdForm">
<div class="form-inline">
<label class="control-label" for="commonage_id">Enter Commonage ID:</label>
<input id="commonage_id" type="text" class="form-control" autofocus="autofocus"
placeholder="Enter ID here " />
<button id="submitButton" type="submit" class="btn btn-primary">View</button>
</div>
</form>
</div>
<span class="glyphicon glyphicon-exclamation-sign alert alert-danger"
id="ErrorMessage" style="display: none;" aria-hidden="true"></span>
<div id="loader" class="loader" hidden></div>
<div id="result_table" hidden>
<table class="table table-striped" id="herdTable">
<thead>
<tr>
<th class="threeTH">Herd Number</th>
<th class="threeTH">Share</th>
<th class="threeTH">Active Farmer</th>
</tr>
</thead>
<tbody>
</tbody>
</table>
</div>
</div>

Answer 1

A glyphicon does not expect to have other content than the icon itself. The problem is that the glyphicon class has more styles attached to it, which are unwanted for normal text. In this case, the font family!
Solution is to put the glyphicon itself in a span of its own, inside the ErrorMessage span.
span[aria-hidden='true'] {display:none}
a:active + span[aria-hidden='true'] {display:block}
a:active + span[aria-hidden='true']::after {content:'There has been an error.';}
<link href="//maxcdn.bootstrapcdn.com/bootstrap/3.3.6/css/bootstrap.min.css" type="text/css" rel="stylesheet">
<a>Press here to show text</a>
<span class="alert alert-danger" id="ErrorMessage" aria-hidden="true">
<span class="glyphicon glyphicon-exclamation-sign"></span>
</span>

Answer 2

You can use the glyphicon icon in separate span tag like this:
<span class="glyphicon glyphicon-exclamation-sign"></span>
<span class="alert alert-danger" id="ErrorMessage" style="display: none;" aria-hidden="true"></span>