This is because of the float: right attribute. Try this
button[type=submit] {
width: 101px; height: 16px;
background-color: #f68830;
webkit-border-radius: 9px; -moz-border-radius: 9px; border-radius: 9px;
border: none;
cursor:pointer;
margin: 0; padding: 0;
position: relative;
}
button[type=submit]:hover::after {
content:'';
background-color: #f68830;
width:6px; height:6px;
webkit-border-radius: 50%; -moz-border-radius: 50%; border-radius: 50%;
position: absolute;
right: 6px;
top: 5px;
background-color: #d9e4ea;
margin: 0; padding: 0;
}