Hello and hope you are doing well.
Benadryl is an antihistamine and can cause drowsiness. Conversely it can also cause insomnia, an inability to sleep. So, wean yourself away from Benadryl and follow good sleep hygiene measures. Go to bed early almost at the same time every day, wake up at the same time, avoid smoking, alcohol, caffeinated beverages and exercise regularly.
Hope this helped and do keep us posted.
I believe there are some natural remedies to sleeping problems. I would also suggest maybe doing relaxing yoga poses or moves to de-stress and calm down before bed. WHen my mind is racing, try and writeI down what I need to do the next day. It might keep your mind from racing. If nothing works i would contact your doctor and see what they say. Good luck!