I am not a doctor, but I have struggled with this same problem and have found a solution for myself that I am happy to share. You have been consuming for a long time, so perhaps you already know this information.
I have noticed that strains that are much higher in THC (almost all of them!) absolutely cause anxiety and that paranoid feeling for me. Everyone is very different in this regards, and I happen to be very sensitive to the effects of THC. I smoke or vape to help control the pain when I feel the onset of a migraine, so my primary motivation is to stop pain and not to get the feeling of being ‘high’. Your body changes over time and tolerance levels can go up or down as well.
The strains that I will list here are lower in THC and in two cases the THC content is almost non existent. I also find that if I smoke it is imperative to only take one puff at a time and evaluate how I feel. For me, 2 puffs on a pre roll with even a lower THC profile, such as Canna Tsu, is more than enough. Everyone is so different in this respect, I just happen to be very sensitive, and perhaps so are you.
The following are low THC, around 5% and higher in CBD:
Cannatonic, Canna-Tsu, Harle-Tsu
Super high CBD profile with almost no THC (zero psychoactivity):
ACDC, Charlotte’s Web
Hope this helps!