FTM baby movement question

Natosha • 💙JARW 2015 💜NLRW JAN. 2019
So when I was around 14 weeks I had this really weird feeling in my lower abdomen. It felt something like a ball rolling out of my lower abdomen and it was just there for a bit. It was hard to the touch also. I had asked some mom friends of mine and they had suggested gas but 30 or so mins had passed and I had no gas, no bm and didn't have to pee. We all said maybe it was the baby. Well now I'm 18 weeks and since about 17 weeks I've felt that same feeling while lying in bed everynight. It doesn't feel like flutters or a kick or nudge but like a ball trying to roll out of my stomach lol it gets hard for a little and then it fades away. I'm just wondering if it is in fact the baby moving? Also I'm 5 ft and at 15 weeks the doc said I felt like 18 bc I have such a small torso I wasn't sure either of this might be why it feels like that. Any opinions? Thanks in advance.