Oh Nicole, firstly congratulations on baby #4. There is definitely an echo in here. I went through the first two trimesters just living in denial about this baby (#5). I cried and ranted and raved about how I couldn't do this, I won't cope, What the hell do we think we're doing, and then it hit me one day that this is a litle blessing, and he is coming whether I like it or not and started to concentrate on all the positive things.

This baby was a bluff. I bluffed and DH called, lol. I really didn't think I would fall, I was breastfeeding and it had taken 18 months to get DD#3 and 6 months to get DD#4 so I really thought that he had no chance to get me and gave him one month to get me pregnant (he wants 6). We had flirted with the idea but I really was just humouring him. Well the joke was on me, lol. Mine won't be as close as yours but I will have three under 3 1/2 with two older ones. At the moment my girls are 9, 7, 3, 1 and a newborn.
Having been pregnant three times in the past four years I am very over pregnancy and find it hard to see me ever having a life outside the home again,but I will one day and right now my life is my children. It might be clouded right now but it will clear and you will see that you can do this and having them close can have its advantages. My fear is that the younger three will take all of my time and attention and my older two will suffer, but I take measures to ensure that doesn't happen. It's alot of work, I won't lie to you but the joy is tremendous. Good luck, if you feel you need help take it there is no shame in it and it can help you.