Those two green circles indicate that the link in question has been used in two separate places in your mailing. The click map sees two separate sets of click data for that link, but is confused as to which link accrued which data, so it places the circles together.
For instance, in your most recent mailing, title FEB27_18_OPEN_ROAD_NEWSLETTER, the link https://pelotonmagazine.com/interviews/thomas-de-gendt-workingmans-hero/ appears in two separate places. In one location, it received 175 total clicks and in the second location it received 19 total clicks. This is why the larger circle says 175 and the inner circle says 19. The smaller circle is simply the number of total clicks the second location of that link collected.
I hope this information helps, but please let me know if you have any further questions!