Terriers are notoriously high-strung and often "pull" at their leads before they are appropriately trained. I just want to pass along some advice concerning neck damage.
Please utilize a harness to take the pressure off the neck area. Injuries to the cervical area can be caused by pulling against the lead and stressing the neck. By using a harness, you can better control your dog without injuring their necks and spine.
Good luck!
Deborah