Starlight UFO in sky going in odd directions

There was a bright starlight in the sky and then I realized it was moving upward like a plane. It was right after the sun was setting, the whole sight was about 15 seconds. As it went up it suddenly took a 90 degree turn to the right. I thought that was odd so I kept watching it. It went straight up in the air then dipped down, then back up again like a loop but fast enough it couldn't be a plane as if you were drawing with crayon in the sky. It went steady up and to the right in the sky. Looking East near Mill Creek.