I did it on my own too. I will say that when I had my first baby, I was definitely overwhelmed. I was really anxious. Even though I'd baby sat a lot and been around babies, there is something about the feeling of utter responsibility when it's yours! I felt like I was keeping the baby alive 24/7. LOL But managed and after a couple of weeks, it was more and more natural. I think if I were to have someone come and stay, it only could be certain people. The ones you can let it all out with, that don't irritate you on a regular basis, etc. My mother in law would have been a no go in that regard. ha.
With both we did not have anyone come to help after the birth. My husband took a week off to stay home, but I really didn't want anyone there. I wanted to be home and resting. My MIL did come one day to clean my house and watch the baby so I could sleep, but I ended up cleaning too because I felt bad LOL