tmi but baby's kicking my butt? πŸ˜‚πŸ˜…

So I'm 33.1 weeks and my baby recently started a new thing today. ???Kicking??? My butt (hole). He's head down, so maybe he's head butting me, not sure. But I've never felt this before and was wondering 1.if this is normal and 2.could this imply labor is near? I've been getting very tight and sore "down there" too. He tried coming at 24 and 28 weeks so they're expecting him early. Just wondering if anyone else has experienced this!