When should I feel the baby kick?

I am 15 weeks as of today, and have been reading my books and getting my daily newsletters keeping me informed. But some things I read say at 16 weeks I should feel the baby kick if I haven't already. I guess I I am being paranoid, but along with that and not having felt anything, I am also not even showing, at all. And at my 16 week appt. next week they said they are going to measure my belly, weeell I don't have one! So what will they do then? Just curious y'all, any advice would help, thanks to all!