Tylenol is the #1 liver eater in the US next to alcoholism, medical fact.
I take 3mg of melatonin or OTC sleeping pills which have the same ingredient as Tylenol PM minus the Tylenol. Melatonin works fine for me.
If your breathing is labored check your blood pressure, next consideration is that your gut is so full that its pushing against your diaphragm. Frankly I dont shoot for more than 20-25 pounds per cycle, none of this 40 pounds biz some folks shoot for, I think its unhealthy.