I understand the theory. The problem is I don't associate bed with anything other than sleep, I implemented that practice years ago. Now I'm actually question

I understand the theory. The problem is I don't associate bed with anything other than sleep, I implemented that practice years ago. Now I'm actually questioning it, I did a lot better when I could fall asleep watching boring documentaries on YouTube. Now I watch documentaries until I get tired, but after getting up, going to the toilet, having a drink of water, brushing my teeth, all before hitting bed I'm wide awake again.