The only time I've ever seen a deer just walk away after being shot, he collapsed about 15 yards from the impact.

To answer your question, I have no idea if you hit him or not, but a shot "somewhere in the ribs" is not a very good indicator of a well placed shot, especially at 30-35 yards. So even if you did hit him it could take a while for him to die, which means you may not want to push him further away by tracking him to quickly.

If you did shoot him there will be blood somewhere, you just have to find it.