Just FYI - Tylenol PM has Benadryl in it to make you sleep (diphenhydramine). Besides all the good advice below, there is a way of meditation that is just opposite of the focusing on 1 thing. You actually allow all those worries and stray thoughts to come in but don't give them any attention. The imagery is that you are by a river with perhaps a nice weeping willow over it, and as your thoughts come to you, picture them falling onto a leaf that fell from the tree in the water, and watch them drifting down the river away (or over a waterfall away out of sight). Be aware of all those random thoughts coming in, but just let them come into and out of your conscious thoughts. So the shopping list for tomorrow, the bills you have to pay, the worry about a child, the worry about money, let it all come to you, even if the thought has drifted away on a leaf and comes again.
I do that, as well as measured breathing: count 1,2,3,4 while you breathe in, hold it for 1,2,3,4, then breathe out 1,2,3,4, wait 1,2,3,4, or whatever count works for you. That is similar to the focusing on 1 thing, plus you get some deep breathing done. Good luck.