I do this sort of thing too. I don't think that a reaction on that scale could be described as 'just a teen thing', though the whole business of gaining feelings of comfort from certain objects and having a need to keep them with you all the time is quite a common AS trait, as far as I know.
I have an attachment to my phone, but it's not just because I'm comforted by the phone itself. The reason why I'm so attached to my phone is because of the purpose it serves: I'm very frightened of being cut off from certain contacts, and of getting stuck somewhere without a means of calling people for help.
Of course, it can be problematic developing such an attachment to that sort of object, because phones can break or get lost, and the network can go down. And when these things happen, I go out of my mind. Last night, I had a meltdown 'just' because I couldn't get a signal for a long time.