I have a similar issue on my website,
On type=“IN/Share” script for the button, the data-url is being ignored altogether. No link shortened or otherwise is displayed on the message UI.
On standard status update links, the link is not being shortened and is therefore exceeding the 140 characters. On submission, I am getting the “ops! Your tweet was over 140 characters.” message. Why is the t.co shortener not working.
The code used can be found here dev1.mycountdown dot org/test.html