Plymouth Crown Court was told Stevenson entered the shop on March 30 at about 7pm.
The woman was in shock and instant fear when she saw he had a knife.
‘Something inside me kicked in (that) I partly regret now. I subconsciously thought "why should you steal my hard-earned money, the time I have to spend away from my family to get it"?
‘I won't let you take what little I have in my till. I grabbed him. I don't know where my strength came from, but I grabbed his wrists and started pulling him out of my pride and joy - my shop.
She suffered delayed shock and was forced to close early for a number of following days out of fear.
Stevenson has been sentenced to three years for the robbery and one year for the attempted robbery, to run concurrently.