Shana-
You are perfectly normal. I think because we know of all the potential issues our children MAY face we start to over analyze every little thing. Our daughter has been home over 2 years and I STILL worry...newest worry is she seems too smart...huh? ...I know it doesn't make sense but I am worrying maybe she has some weird issue...so I force myself to stop.
Our daughter stayed in her room, on her bed not calling us or getting down until well after she turned two (adopted her at 11 months.) Then she would get off her bed but not leave her room or call for us...then she would knock on her door, from the inside like she was looking for permission to leave. Finally, now at three, she comes out on her own...not always a great thing!
We talked to her for over a year about it being OK to call us or come out.
Alex will only cry if he has a dirty (stinky) diaper in the morning...other than that he will play quietly in his crib and he's been home 8.5 months. Now, if he's hungry in the middle of the night or loses his binky...he screams for me...still an almost nightly ritual!!
Try to relax and realize that worrying won't change things...he is your son and if he does have an issue, you will deal with because he is your baby...just like any other mom would!!
Take Care-