Our first child was the most high need child I ever ever have met. ( and I have been around so many since I used to be a childbirth educator.) Literally I could not set him down hardly for the first 2 years or so of his life. I even often slept with him in the sling since he would wake a scream otherwise. When he was down he never ever stopped moving and getting into things. ( @ 17 months I went to the bathroom with out him and came out to find him on top of the fridge!)
Thank GOD he nursed so that there was some sit down quiet time, but even that was hard since he would nurse sometimes for 2 hours or more straight and sitting still is super hard for me too!
I got pregnant with his sister, ( on purpose) when he was almost exactly 2 years old. He changed much during the pregnancy as he was growing up and some things got easier. Still he was a real handfull!
What worked best for me, I continued to nurse him and so I would nurse them both at one time so then @ least I knew where he was! I really really childproofed the house. I prayed often and thankfully did not have to work outside the home very much. ( had my own childbirth ed practice) during her first year.
I did as much active with them both as I could. I will say that at times HE got more attention than she did since he is more demanding than her and it is still true. I have to work very hard to make sure she is getting the attention she needs. She is much calmer and less needy and very obediant and easy to take care of so I have to go out of my way to be sure she is getting all of the attention she needs.
I am very thankful she was not my first child since I think I would have somewhat neglected her as she would not have asked for anything. Having Sam first I was aware of a child's needs and payed lots of attention to that and so often was attending to things even when she did not ask. If I had had her first I would have been unaware that she even had some of the needs. I always say that Sam got me trained properly.
It will be harder with 2, but would always recommend it! I too have no family here and did not have anyone to help me with kids and my husband is often out of town on work. I have built my own support system by finding other like minded moms ( going to mom's groups and Le Leche League) and by getting help that I have hired to come help. If you can't hire, advertise on craig's list a swap of help and interview until you find some one you click with.
If you really want another child you will do fine, you will be surprized at what you can accomplish but you will do fine and be glad that youd did.