I'm a new Mom and new to this site. Derek is about 6 1/2 weeks old and will not sleep on his back. I am terrified of the increased risk of SIDS for babies that sleep on their tummies, but I don't know what to do. I tried to put him to sleep in a a positioner, but he startles and wakes up. AND...he HATES to be swaddled! What should I do?