Movement

Me this weekend at my in-laws, to my husband: "I felt the baby move this morning."

H: "You did?!" [w/ an instantaneous, lit-up grin]

M: "I think so..."

H: "What did it feel like?"

M: "Kind of like a muscle twitch, only one I wasn't moving."

I really have no idea how to explain it. Part upset stomach that isn't gas? Kind of spasmodic and innocuous, but could possibly become injurious if it increases in force? I don't go along with the whole 'butterflies in my stomach' feeling. I know no butterflies that could give me that sensation - and besides, I've been in too many nerve-wracking performance situations to confuse that feeling with 'complete other being moving inside me.'

How wrong of me is it to rejoice in having felt movement at 17 weeks when all the books I read said 1st time mothers normally feel it at 18-20 weeks? I can't tell if I'm rejoicing in my apparent over-achievement or Baby's. Either possibility has frightening soccer mom implications.