J.H.
The best thing you can do is to try to get both children on the same nap schedule. I realize that a two week old will sleep alot more than a two year old, but if there is one long stretch in the day during which you can get them both to sleep (so that you can rest), it will be better for all of you. My boys were 2.5 years apart and this did wonders for my mental state. :)
How about reading a book to your toddler while you breastfeed? He doesn't even need to sit still for that, but can sit beside you on the sofa and look at the pictures while you read if his attention span will allow for it. You can also keep him in the room with you and just make sure that he has enough toys to keep him occupied while you are feeding the baby. Try giving him new things to play with, such as spoons, cups, and bowls, a shape sorter, large blocks, several hats, or an old purse or bag with interesting items inside that he can put in and take out. Also, if your two year old is feeding himself, you can put him in the highchair and give him a small, easily eaten snack (just keep him in your sight while he's eating).
Bottom line, things will get back to normal for you. A new baby can be chaotic, but once things settle down, you won't feel so frazzled. I can also promise you that your older son will not remember this time, and will NOT feel as if you didn't pay enough attention to him, so don't worry about that!