Anyone?

Brittany • 19. Engaged to the love of my life. Been together for 2.5 years. 2 amazing step kids. And a ftm , to our son who was born February 3, 2016. ❤
For the past 2 days I have been feeling my son tighten up and then it releases.. I'm not sure what this is! Anyone else have this problem and know what it is?