J.S.
The same thing happened to me and theres nothing wrong with how you put him to sleep. Nathan fell asleep on my chest up until a year as well and I also questioned if this was ok, because I wanted to just go to bed, but I asked my mother in law about it and she told me "they are too precious and grow soooo fast, enjoy it before its gone"
My point is, right around 11.5 mo. he wouldn't fall asleep on me anymore and from then on, I knew that it was time to adjust. If he likes a special blanket, nuk, music (little radio), bottle (with water)...put those things in the crib with him. Milk bottles is a bad habit, so if you use water, they will no longer need the bottle. Put a night light in there too. Theres so many different ways and only you will know what to do if you try new things.
Good luck and let me know how it goes!
(BTW, my son at 14 mo. fell asleep on me yesterday and I was in heaven!!!!)