Yes, please stop.
Back pain from jumping on the trampoline indicates compression of the spinal cord. Compression of the spinal cord discs will either create herniation of the discs or crush the discs.
There are two body types that contribute to such compression. One body type is a torso that is overly heavy or obese. The other body type is a disproportionally long torso compared to the length of the legs, and the long torso and spinal cord cannot maintain a straight posture. Any slight bending of the torso where the center of gravity from the head down along the spine is off center will cause compression of the spinal discs.
In trampoline exercise, the torso must be maintained vertically straight and the center of gravity of the body must be kept at the center.
The physical attitude of the head is very important in keeping the center of gravity of the upper body vertically centered. If the head is looking down or tilted backwards, the weight of the head itself slants the center of gravity, and the off-center weight of the head itself will be enough to cause spinal cord compression.