Intense pressure in butt

Hi, so I’m exactly 37 weeks today (due 12/30) and I have been having severeeeee pressure in my butt all day and night. I can’t poop, but that’s what it feels like. If I stand or walk around, it’s better (not great but better). I sit all day long at work and then drive an hour home (more sitting) and I’m absolutely miserable. I cried the whole way home today while trying not to crash bc I felt like my anus was falling out. Wtf is this? What do hemorrhoids feel like? I’ve also had a ton of tightness in my stomach (get BH a lot but even more today). Am I dying or is this really my life for the next 3 weeks?