Four month slight flat spot


So we went to little ones 4 month check up and the pediatrician said she’s developing a slight flat spot on her left side. She sleeps on her left side so he said to flip her and make her sleep on her right. How do we prevent this flat spots? I hold her she does tons of tummy time, I wear her. Literally the only time she is on her head is when she naps. She hates swings and all of that jazz. FTM and I can’t help but to feel like a failure or a bad mom. Some one please help.