My dog is a male puggle, he is around 9 years old. We’re fearing that he’s going blind, he keeps running into chairs, doors, not wanting to go down stairs, missing pieces of food. He’s also whining constantly when he’s not sleeping. We feed him half a cup of food 3 times a day, so i don’t know if it’s hunger. He’s even reverted back to grabbing stuff from the counters, rooting in bags, etc. He especially likes Gum. He’s gotten into tons of chocolate, grapes, waffles, brown sugar, and even rat poison once, I just hope it’s not slowly killing him. I really don’t know what to do.