Baby keeps pushing

Ugh I am at a lost. My son is 2 weeks old and lately he's been doing this pushing thing where his face turns so red and he seems so uncomfortable. I thought it was constipation at first but he's poop like normal for the most part. I even tried karo syrup to see if that would help and nothing. I got the ok tp.try gripe water and that didn't help either. I'm at a lost. He sees his doctor tomorrow but just wanted some input.