Yes - I think it's too soon!

You've already called to check she got your email - and seriously a week is no time at all - I wouldn't prompt my own agent so fast. I don't think prompting at this point is going to help.

<Added>

And I don't think it will make any difference whether it's a paper or an email submission, if that makes you feel better. Paper subs are just as likely get buried under a mountain or forgotten at work.

Many agents use e-readers now anyway.

Yes I'm sure you're right......