Help Me Walk And Run Again!

Hi! My name is Luke. I'm a Great Dane, and mummy says I'm a very good boy. I love to run and play with my rescued greyhound brother and tripaw sister. I let them win when we race. I love my mommy, she works two jobs so me and my greyhound siblings have the best of everything. I think she works too hard. I drool on her so she knows how much I care. I'm making this page because I need help. I know my mommy is very worried and this makes me sad. I hurt my back badly. It hurts me to run and jump, and makes it hard for me to lie down and get up. The doctor took pictures of my back (I tried to tell him it is not my best side, but he took a lot anyhow. He must like backs) Mommy said I might have a compressed or ruptured disc. I don't know what that means, just that it hurts. Mommy said I get to see a specialist to do an MRI. I hope MRI is a tasty treat. I like treats! Mommy said I might have surgery to help my back. I'm scared of surgery but I'm more scared that I'm having trouble walking. Sometimes I even fall. I am trying to be brave. If surgery is good then I can run and jump and go for walks again. I love walks! Sometimes there are squirrels. I love squirrels! Mommy said the surgery will help me potty outside again. I'm so sad and embarrassed that I can't tell when I'm going potty because my back end is so messed up. I keep pottying in my sleep on mommys bed. I feel so sad when I do, but mommy always tells me "it's ok" and I'm a good dog, then helps me go outside. She is the bestest mommy ever. I know mommy is worried because just the MRI is $1800-2400, and then the cost of back surgery too. Mommy is working two jobs and selling all her things to help me get better, but I know she could use help. If there's anything that you can spare to help me run and play again, please donate. I'll give you a big wet kiss and shake your paw if you do.