Like most people said, taking Tylenol PM is not a good idea. If you are not in pain, why take acetaminophen which can harm other organs? I have chronic, CHRONIC, primary insomnia. Done the whole sleep lab thing, and tried every medication prescribed and OTC, and every combination of them. Believe it or not, the best results for me after 10 years of trial and error is:
1) avoid EtOH before bed - nightcaps do not help you stay asleep, you may fall asleep quicker, but will wake up;
2) no napping is also a good idea; and
3) the medication that worked for me best is a combination of 1 pill of doxylamine succinate (found in some Unisom, others have benadryl so stay away from that) and 0.5 of klonopin. You fall asleep with 30 minutes, no awakenings (or few brief ones), and no hangover.
Everyone is different, so not sure if the same for you. But I have tried everything.