Clipped Tweets & Missing is.gd URLs

I started noticing this yesterday. On one tweet, I was posting a quote that fit within 140 characters -- but when I hit enter, it only included the first sentence of the quote (46 characters).

Today, I posted another Tweet that was within 140 characters -- Twitbin only included 54 characters.(I didn't delete it, so you can see it here: http://twitter.com/bethanybob/status/...)

According to the live "twitbin" Twitter search, I'm not the only one with this problem: http://twitter.com/Rosengeranium/stat...

Finally, I'm not sure if this is a separate problem or related to the above. When I right-click a page and click "Tweet This!" Twitbin comes up with the handy dandy short URL already in the "Tweet tweet" field (such as http://is.gd/jbr8). I have twice attempted to describe the page I'm linking to before the URL -- i.e. "This is @Rosengeranium's Twitter page: http://is.gd/jbr8" But when I hit enter, Twitbin often removes the URL at the end of the Tweet. (I think I had one successful attempt early on, but it hasn't worked in the last few days.)

I hope this helps. :\