Baby Moving Or Muscle Spasm Is This Sensation I Am Having The Baby Moving?

Is this sensation I am having the baby moving? - baby moving or muscle spasm

I am 17 weeks pregnant. And it is these days, I feel like a tugging feeling in my stomach. Sometimes, no pain involved. I wonder: Does the child have to move or some kind of rare muscle cramps? Needless to say, this is my first pregnancy.