J.C.
I have two children who are also really close in age. I have 2 girls who are 14 months apart (the older was 6 months when we found out about the younger), and I wouldn't trade them for anything. I did have to make a few adjustments because of the pregnancy (on doctor's recommendation I quit breastfeeding) but now I look at them and know that I couldn't have made a better decision. They are now 6 and 5 and other than normal sibling arguments are the best of friends. It is possible to get through this and it will be okay. I am not saying that it will be easy, but in the long run it will be worth it.
J.--SAHM of 6 (soon to be 7)
If you want more specific adivce please message me and I would be happy to give you some tips on how to make it through the first few months.