How to vertically align text field with it's label and button - twitter-bootstrap-3

Question

I'm basically trying to have this kind of layout:
Label TextField Button
So e.g:
Number of copies [5 ] [Add]
Thought that would be really simple to do. But I've struggled for a few hours now, and this is the closest I've come, which is absolutely terrible:
Here's my code:
<div class="row col-md-12">
<form class="form-inline pull-right">
<div class="form-group">
<label for="numberOfCopies">Number of copies</label>
<input size="1" type="text" class="form-control" id="numberOfCopies">
<button type="submit" class="btn btn-primary">Add</button>
</div>
</form>
</div>

Answer 1

At first some Bootstrap-Basics:
your 'row-div' should be wrapped by a 'container-div'
row and col-xx-x classes need to be on their own div-tags
as you can see at the example below, you could easily get this done using css.
With display: flex; we get all elements of the form-group side by side.
With white-space: nowrap we 'tell' the label to be shown as one-line only.
Using the margin-tags we will get the elements to the right position.
To learn more take a look at the documentations of display, white-space and margin.
I think the usage of input-groups could be interesting, too. Feel free to ask per comment, if anything is unclear.
.form-group.flex {
display: flex;
}
.form-group.flex label {
white-space: nowrap;
margin-top: 7px;
}
.form-group.flex input {
margin: 0 7px;
}
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css" integrity="sha384-BVYiiSIFeK1dGmJRAkycuHAHRg32OmUcww7on3RYdg4Va+PmSTsz/K68vbdEjh4u" crossorigin="anonymous">
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/js/bootstrap.min.js" integrity="sha384-Tc5IQib027qvyjSMfHjOMaLkfuWVxZxUPnCJA7l2mCWNIpG9mGCD8wGNIcPD7Txa" crossorigin="anonymous"></script>
<div class="container">
<div class="row">
<div class="col-md-12">
<form class="form-inline pull-right">
<div class="form-group flex">
<label for="numberOfCopies">Number of copies</label>
<input size="1" type="text" class="form-control" id="numberOfCopies">
<button type="submit" class="btn btn-primary">Add</button>
</div>
</form>
</div>
</div>
</div>