Plagiocephaly?

My son is 6 weeks old, will be 7 in 2 days, and his head is awkwardly shaped. I think it is due to sleeping on one side of his head every night since he prefers that side. (Right side) so now he has a flat spot and a bulge on the left side of his head. I tried to rotate him from side to side since he was born but he always ended up on his right because of a bad habit he developed and I couldn’t keep up with it at night while he sleeps. What could be done to even out his head? Is it too late as a 7 week old to help the shape? Could there be a problem if this issue isn’t fixed in the near future or has any momma out there experienced the same/similar thing?

Thanks everyone!