I dunno... sounds like you have it all figured out to me
I have 4 and would still never dream of letting a baby CIO. And OMG! Even the thought of letting a 7 week old infant CIO is heartbreaking
I don't know why some people would equate picking up a crying infant to inexperience.
And if it makes you feel any better, I'm a serious BTDT mom & not one of my children were left to CIO. We have no sleep issues at all. My 7 yr old goes to bed at 8 (no questions asked), my twins go to bed at 7 (no questions asked) & they nap for 3 hours in the middle of the day happily.
Now with my 6 month old. I thought that child would never sleep
Since he was about 4 1/2 - 5 months old he was an all night nurser. He was on breast at least every hour. It was killing me. But I knew it was what he needed and just because it was night time, didn't mean my parenting job was over. So I kept up with his needs and now I'm able to set him in the pack n' play in our room at 7 pm while he's still awake and he can fall asleep on his own. He only gets up once at 3 am to nurse and he's back down at 3:30 until 7. And he's sleeping like this without ever letting him CIO once
Really, it just comes off as completely strange to me that so many people feel that every infant should sleep through the night. It's just not natural for most. There are physiological reasons infants wake frequently through the night.
Here is a really great link on infant sleep
http://www.askdrsears.com/html/7/t070200.asp
Try not to let other people talk you into doing something that doesn't feel right to you as a parent. You know what's best for your baby. I have found that a lot of people feel the need to push their parenting on others for two reasons... 1) they genuinely feel that some kind of harm could come to a child... This is obviously not the case with you
2) because they feel insecure about choices they made as parents and by having other people do what they did it validates those choices... I think this may be your problem
Hang in there mamma!