Question about Pembroke Welsh Corgie?

My 16 year old Corgi has been struggling lately. She hasn't been able to make a bowel movement in 3 days. She won't eat her dog food, only scrambled eggs. She's drinking very little water. After she eats, she goes to the lawn like she's about to go, but nothing ever comes out of her. She has urinated, and doesn't seem to struggle with that. For a while now, it's seemed like she's had trouble with seeing and hearing. Yesterday, I put on rubber gloves and looked at her anus to see what's wrong, and it felt like there was an extremely hard lump in one area there. Last year, she had 14 of her teeth pulled because they were infected, so it's hard for her to chew. We wondered what is wrong with her, and what you think will happen to her.