Pre-pregnancy I could not wrap my head around what it would feel like to have a baby in your belly and moving around. 23 and a half weeks in, I still don't think you can really totally imagine it until you've been there, done that. However I'd like to try describing it. And since I was incredibly curious before I was pregnant, I figure there's at least one other person out there wondering the same thing.
First - The first time I "felt the baby" was during yoga class doing an on-my-belly pose. I was still in the clear for stomach laying and whatnot so I wasn't too worried about it. But this one time I laid down on the ground and it felt like I was laying on a small nerf football. Right below my belly button. It was kinda a "princess and the pea" type moment. Like I knew there was something there but couldn't quite figure it out. (About a week later I confirmed with my nurse, yup, that's a baby. I then stopped doing said on-my-belly pose). I think I was about 18 weeks along at this point.
Second - When I started feeling Baby move, it didn't feel like flutters at all. It felt more like the less-appealing analogy people make, gas. It sorta felt like when you are really hungry and your stomach twists in knots, except without the hunger pains. Just like a part of me was doing something in there (something pretty darn important). I think this was also around 18 or 19 weeks.
Third - The next phase of baby movement felt like someone playing pool or ping pong in my belly. There was nothing graceful or detailed about it. It was a like a whole mass moving all at once. Somersaults. Stronger than the hunger pain-esque feeling, but again, not precise.
Fourth - This is where I am now. I can feel punches/kicks but I can't tell which anything is. It is definitely more distinct, detailed movements as opposed to feeling like the whole kid is moving at once. It's kinda like if someone taps you on the shoulder, just from inside your belly, which yes sounds really strange but it feels remarkably similar from inside your body as it does from outside. Sometimes it can be felt from outside my belly too but that isn't very consistent yet. Also, now he MOVES, and pretty consistently. Every morning and every evening, right after I wake up and right before I go to bed. I'm still not sure if he's actually moving tons more during these times or if I'm just less busy and more aware of it.
I was kinda worried having a baby move inside me would feel really foreign or alien. Fortunately, it does not. I think part of that is because it comes on so gradually. It's not like one day everything is still and the next day you are getting boxed and drop kicked.
So when you have a baby in your belly, know it will probably feel pretty normal and natural which is exactly what it is.