2 days ago, My son stepped on my stomach && also sat at the bottom of my stomach. And I can't say…

2 days ago, My son stepped on my stomach && also sat at the bottom of my stomach. And I can't say how much pain I've been in, because it's gotten to the point where it feels like contractions!

Yesterday night I noticed that my lower belly has this hard ball at the bottom.

I'm currently TTC, Ive been really active. Does this sound like something I should get checked? Or will it pass?