To start off, other than the 2 problems I’m concerned about, my little Mordecai is acting, eating, grooming completely normal. A while ago, I was watching my bun sit and groom himself (sitting on his hind legs) when all of a sudden, he stretched his back out, opened his mouth wide, and shivered/trembled his bum. He did this twice in a row. I immediately went over to pet him and make sure he was okay and I gave him some hay and checked his bum to see if maybe he had diarrhea (since what he did looked like he was trying really hard to push out a poop), but I didn’t see anything and I checked his belly to see if he was bloated but it felt normal. This happened again today, and in the last week or so I’ve noticed that he has started thumping. Sometimes it will be while he’s running around– he’ll run, stop momentarily to thump the ground, and then keep running– or it’ll be while he’s in his cage at night. He’s a 5 month old Holland Lop and he’s not neutered. I’ve had a sniffles problem with him but after a round of antibiotics, he has been cleared up since. What is causing the trembling and the thumping? Are they related? Is my bunny okay?