After hitting the spring into the second camp, my seed was inside the camp but the balance stick was stuck below the camp. I took a screenshot, but accidentally overwrote it, so you get an mspaint recreation of the events:
I couldn't move the stick up, but could move it down. After moving it down far enough my seed fell down, and I could resume moving up again. Unfortunately, as you can see in the screenshot, the spring was already sprung, so I was stuck.