What are the symptom differences between a groin strain and a hernia? would they be similar?

Yes: Symptoms can be very similar for both a groin strain and hernia. Usually with a hernia a physician or patient can feel a bulge at the site of the hernia. With a groin strain, no bulge is felt. However small hernias can cause significant symptoms and they can be small enough to not feel a bulge very well. A good history of the pain and exam can help differentiate.