Disbelief

So..I’m 18 weeks pregnant. First pregnancy. And I’m a bigger girl, so I’m expecting to not show much. But I still don’t believe I’m actually pregnant. I’ve seen the ultrasounds and heard the heartbeat but I haven’t felt any “symptoms” or noticed my bump growing even a tiny bit. My mind is pretty much refusing to believe I’m pregnant even though I know I am. Like really…Saying I’m pregnant sounds like I’m playing a disgusting joke on someone. But I AM pregnant. I don’t really know how to word things…but have any other moms felt this?