Jocelyn,
Welcome to the Forum.
You cannot run a computer that is wet, regardless of the source of the dampness.
At the least, you have to open the notebook as much as possible - remove the battery unless it is sealed inside, and then let the notebook dry out for several days. You might try using rice in a tightly meshed bag to help draw out any wetness. Wrap the notebook in the meshed rice bag and put the whole thing in a dry, well ventilated area. Do not put your notebook in an oven, on a stove, or near any direct source of heat. Do not put the notebook in direct sunlight.
Because of the source of the wetness, even assuming there is not hardware damage, you may not want to run the notebook after it dries out. If I were you, I would dry out the notebook and then take it to a reputable repair shop to have it looked at. It may be possible to clean the notebook well enough that it can again be used. This does assume that there is not hardware damage, which is a distinct possiblity. This is not because the source is Urine necesssarily, it is just that notebooks and water or liquid of any type do not get along.
If you have a warranty on the notebook, or even if you do not have one, you can always call HP for help.
Contact HP – USA - Phone Assistance
Good Luck!