I'm pregnant for my first time (19 weeks). I wasn't sure at first but I would feel some bubbles that usually were followed by gas. Last week I noticed the feeling lower in my uterus area and no gas followed. I went to my doctor last Friday and he said yup, I have a very active baby and I'm feeling her move :) hope that helps! As for sounds in your belly, I've not heard that that's a thing but I keep getting told every pregnancy is different.
I'm pregnant with my second and I'm 20 weeks and I heard the same with my first, it is the baby and you can hear it because it's moving but you can't feel it yet as your still very early