Feeding your baby

My LO is 7.5 months old. Our last doctors appointment was at 6 months old. His doctor told us to wait until at least 9 months before giving him anything other than his bottle. I had called this week to ask about maybe frozen fruit in his tether and he freaked out as if I was a terrible mom for even thinking it was ok.

Even though the doctor says no I started giving him rice cereal at dinner, he started to wake up in the middle of the night hungry with just his bottle. Since starting the rice cereal he sleeps throughout the night again.

Am I wrong to feed him anyway??