Impossible to know from your description exactly what is going on, but you should go see a doctor, as soon as possible.
When men nut it feels like a pulse and it feels like releasing built up urine
The kidney is "designed" to 1) not leak proteins and 2) to reabsorb any that do get into the urine.
Usually concentrated because of dehydration
not like a gas leak but yes
not like a gas leak but yes
It is sometimes normal if they have been pregnant for a while.
Because urine has urine in it.
Could possbly be an infection, see a Dr.
Their suits just absorb it. So in other words they just go when they feel like it.
I don't know about a pregnant dog, but urine leakage is a sign of diabetes, get a bottle of diastix glucose test strips and test her urine.
it smells like urine