We didn't see Barnabas bite Nathan, did we? So he probably bit him on the wrist, so Ben wouldn't get the wrong idea.
Shouldn't Millicent have been locked up and under guard? Never mind, I always enjoy seeing her. It's hard to keep track of whether she thinks Barnabas is dead or alive, but who can blame her for being confused on that point?
For all that Barnabas talks about how irresistible the craving is, I'm shocked that he couldn't resist today's doxy. For heaven's sake, he had just guzzled some blood out of Nathan a couple of hours before! And he had experience with resisting the craving, and he had strong hopes that he would cease to be a vampire in under 48 hours. This may be the most unforgivable thing Barnabas ever did.