Babies first kicks!

So I'm at work, and all of a sudden I feel a little thump. It reminded me of a muscle spasm type of feeling. So I sat still and noticed three thumps back to back. Then a few mins later a couple more. It's really low, like its right above my vagina? It's the same spot she did the ultrasound at. Is that the baby kicking!? I'm 17 weeks and 5 days!