Without Earth’s gravity weighing down the human body, you can get space sickness, also known as space adaptation syndrome.
It’s like motion sickness but coupled with headaches, disorientation, intense discomfort, and possibly vomiting and vertigo.
About half of everyone who winds up in space gets space sickness.
It isn’t the lack of gravity but rather the sudden change in gravitational force that’s making you sick.
Once you adapt, you’ll be just fine.
The good news is it only lasts a few days.