I didn't make it!
You could play the tutorial, they explain a lot about how to take care of settlements there. If you want to bring an army unit back to it's full strength you have to send it to a city which can recruit this kind of unit and repair it (button next to the recruit button in the city-view). If you have problems with money just scrap some of your more expensive units, buy roads and markets and sell your map information.
If your gains are negitive, take a look at what's being spent on what, but I bet it's either A. You have too large of a army or B. your simply building too much, I suggest you cut back your army, and build more trade roads, farms docks and mines.