Don't "dabble". Do a Whole-30 trial. The more you comply with primal/paleo completely, the easier it will be to see how your body responds and what adjustments you need to make. Set controls so you know what might be causing problems (ie. protein-filled breakfasts at a specific hour, waking up the same time everyday, no snacking whatsoever, no eating after a certain hour etc.). Remember that you are not one-size-fits-all and you might need a different regimen than someone else (maybe it ends up that you need multiple meals through out the day instead of 3 strict meals/day).
And keep reading! There are many +50s out there, even here on the forums, that are primal and succeeding. I've even seen people in their 70s around here. You might want to read into Adrenal Fatigue or do a forum search for it.
I hope this is somewhat helpful and/or encouraging

I think it's funny that you seem to think that only young people are doing primal because 1. you're not old and 2. I thought the opposite when I first joined!
