I need so sav help!

[Tyguy35]

Hello, I have had my save for almost 2 years since he was very tiny. He recently stopped eating and pooping. I took him to a vet and the vet found nothing even when looking at an x Ray he said he found nothing. I can see that my savs belly is getting larger and I can feel something in his stomach. It almost feels long and hard. My sav use to walk around bask sleep walk around bask sleep repeat. He never dug or cared for digging at all. Now since he stopped eating a pooping it's all
He doesn't he's extremely active and digs non stop all day long. What is going on? Right now he's digging a huge hole like he does everyday then he leaves it and digs more. Help please. Here are his X-rays.