Is it possible for me to have felt my baby today!?

I'm 13 weeks pregnant an today I felt (while I was walking to a filing cabinet) some weird "rustling" or fluttering-(not like gas either…this was different) in my lower abdomen? I can now feel the top of my uterus above my pelvic bone and that's where I felt the "movement". Is it possible to have been the baby? It's been very, very active on all my ultrasounds!