Oh sweetheart, I reckon if you asked any mum on the street and they were brutally honest, they'd tell you the felt the same. Very very normal.
Right up until DS was born I felt like that, but you do manage. In fact it only takes a very short time to forget what it was like 'before'. Like Mel said - you just manage.
I also totally agree with Rivlas, experience makes the difference.
We have a nearly 3yr ages gap and it works perfectly for us. In fact that's how long I'd wait until I thought I wanted another (unlikely but hey).