I think you are right when you say that Harry was just so relieved to have been accepted that he couldn't resist contacting his friends. Severus being Severus, though, will always be suspicious of anyone's intentions, at least initially. Hopefully Harry will cure him of that habit in the not so distant future with plenty more terms of endearments and all their associated goodies... :)

Thanks, as always, for taking the time to both read and review, soleo. Your gorgeous comment meant the world to me.