I have a rebounder and a destroyed back. The quality of rebounder makes a huge difference. I started with a cheap $20 Wal-Mart one and it made the base of my skull, knees, back, as well as everything else in my body hurt. Then I was reading on rebounding sites how the more expensive ones are worth their price. They were so absolutely right. They also said to start very slow. Only spend a minute or two each day doing a very low health bounce, almost to where you don't leave the mat and work your way up. (The health bounce is where you come down on you heels first, then toes.) Here is a video to give you an idea /youtu.be/mMpg7LXcZus
. I also have the spring loaded kind, not the bungy.
You're moving lymph, so it would make sense if you do too much, too soon, you may feel terrible.