Took him straight up to the vets this morning ( was dropping of cat to be speyed there anyway....who turns out to be about 4 weeks pregnant with about 4 kittens!! ).
Vet gave him a thorough examination but not conclusive what is wrong with him. His guts have stopped doing anything. His back legs are very wobbly. He can stand but when he walks he is staggering. He is still very alert and interested in what is going on around him. Vet suggested rhody poisoning (but he doesn't have access to any), twisted bowel or spinal cyst. Spinal cyst is more common in orphaned lambs (of which he is on) who have not had enough, if any, colostrum. He has had painkillers, antibiotc and multivit jabs. We have ]removed him from the paddock, given him hay and water and penned him off in a shed with outdoor access but no grazing. It's a case of waiting and watching to see if any improvement or deterioration. Having just checked him, he is still doing a bit of teeth grinding and it's not nice to think he is in pain.