I had a labrador that did this and to relieve the pressure i felt of the udder to see how it felt before I started then I milked a little from her and felt to see if the tightness went away, if so I stopped, if not I continued. ONLY milk enough to relieve the pressure. You are correct she will continue to milk.
Milk production is supply and demand, the more you demand the more they supply. Relieve a small amount so she does not continue to supply more
Milk production is supply and demand, the more you demand the more they supply. Relieve a small amount so she does not continue to supply more