I did this once.
She was about 9 months old; we had moved to a new town where I didn't know anyone; hubby was attending school on the other side of the province and boarding 4 nights a week; I had a head cold and just wanted to sit by myself for a few minutes. But baby kept following me around and crying and wanting UP! Well, we were both crying!
So, I got right in the middle of the playpen where she couldn't touch me. We both cried for a few minutes. Then I got out, and picked her up and kissed her and cuddled her and NEVER did it again.