I agree with people who say you should consult a vet.
But as a side note: baking soda doesn't do shit for odors. That's a myth that was started by the Arm & Hammer marketing team. And it's doubly wrong to use in this instance, because amonia-heavy urine is already basic (high pH). If you want to neutralize it, you should be treating it with an acid like vinegar. Basic chemistry.
Alternatively, pet stores sell litter deodorizers that do work and are safe. I've used one that is made from (I think) wheat germ.
