t.co is still working correctly, but the combination of the page title, the via parameter you’ve added, and the URL after being wrapped with t.co makes for a tweet longer than 140 characters.
“I Used to Have Anorexia and Obsession with Diets. I’ve Recovered but the Paleo Diet Sounds Healthy. Should I Try it?:” is 117 characters.
Your URL is counted as 20 characters at this time – though it displays your whole URL in the box, it’s counting toward only 20 characters.
" via @choosehelp via @choosehelp" counts for 16 characters.
117 + 20 + 16 = 153 characters.