Some groomers will trim your dog's nails for around $10.00. When I do my dog's nails I have someone else hold her on their lap for me. Once you have hurt a dog by cutting the nail too close they tend to be very afraid of the procedure. There is a grinder type of tool that files the nail down rather than clipping it. They come at various prices. It is much safer than cutting but now that your pet is afraid you may still need someone to hold him.
Oster Gentle Paws Nail Trimmer | PetEdge.com