Apart from waking up and insomnia, how do you know when you're getting good- versus poor-quality sleep? And how do you know when you're getting REM versus non-REM sleep?

I find I'm spending a lot of time in bed - probably around 10-12 hours a night. My sleep is a bit better, but I'm still waking up 2, 3, 4 times a night with lots of vivid dreams. It would be nice to reduce the number of times I wake up and to tone down the dreaming (or at least my awareness of all the dreams).

I expect that my sleep will continue to improve over time, but this is a somewhat annoying TBI side effect. On the other hand, I am grateful to be able to get a half-decent night's sleep.