Is there anything on the market , herbal wise that helps calm hyper dogs?

At bird stores they sell Chamomile flowers which calm and soothe birds and human beings to. You could mash some up in a bit of peanut er or wet food at night. Some of it is that terrier they are just always busy looking for things, like rats, rodents its in their biology. Please do check if it is safe for him first. A non herbal is benedryl 1 mg per pound of dog every six hours. I use it for my pugs allergies. Sounds like you are really being a good pet owner so give yourself a pat on the back for that.