The short answer: Being overwhelmed depends on the AI difficulty level and level of aggression. As the CSA, something will not work right at any given time: you will not have available soldiers (=conscription points). Or you will have enough soldiers, but not money. Or you will have enough money, but not as many war supplies as you'd want. It's not frustrating, but rather realistic and a nice challenge.
The long answer: My advice would be for you to select in "options" the 2nd AI difficulty level (not the easiest, but quite easy) and the lowest level of aggression.
On these settings I just finished my first ACW game ever yesterday (as the CSA), by taking Missouri, Kentucky, Cincinnati, persuading the British to land near New York City and then taking Washington DC all of this leading to a collapse of Northern morale in the spring of 1864
But make sure you understand:
1. the supply rules = what to do when a force is out of supplies.
2. Army structure = how to build divisions, armies, army corps = how to make those red percentage points to go away so that your troops can fight at full efficiency
Once you learn these two things, you can really enjoy the game and push the difficulty level up. I know I learned them the way I haven't learned things since college
