I so feel you, I don't know what I'll do if my THC edibles stop working - I use the kind with 5mg THC + 5mg CBN and sometimes lately I do pop awake through them. And I think that good pre-sleep hygiene is important, like lack of screens/caffeine/take a warm bath etc, but if those things weren't the problem to start with, they are unlikely to be the full solution even if they're helpful in setting the mood.
I did notice the other night that my sleep edible kicked in unreasonably quickly for some reason and in the midst of trying to negotiate my night routine while uncomfortably high, I accidentally took a second 5mg gummy because the jar was still sitting next to my night supplements and I was operating on muscle memory. I did sleep like a rock that entire night, I think I got 9 hours. I don't want to double my dose again, but maybe taking 7.5mg instead of just 5 will help? Have you tried upping your THC dose to check?