Main navigiation layout bugs after adding a cart block
Looks like those dots are a content on :before of the anchor tag, to remove them you could add this to your CSS files.

.header-container ul.menu li a:before {
    display: none;
}


This looks like it have been added by Drupal or maybe the theme you are using, i am not really sure, I recommend you read this https://www.w3schools.com/cssref/sel_before.asp to understand more about the before selector.