I have a daschund mix, he is about 3 years old... yesterday we were sitting out in the garden and he jumped up, gave a yelp and has been hurting ever since. I thought he had gotten a bug bite (which has happened before). . I was unable to find any bites on him and he was still not feeling well this morning so I took him to the vet who says I need to have back x-rays, that he most likely has a disc problem...

what is the 411? Do I need a second opinion?

I would do the x-ray,you will be able to see if the disc is blown.Dachunds are very common for back trouble,and sometimes it can result in paralysis,and the x-ray is probably cheaper than a second opinion.Injury to a dachund can happen with him just jumping from a short height,and sometimes a steroid shot will help with the pain and inflammation.Let us know how things go.