Dd has this. She wasn't diagnosed until 12 weeks. She would constantly face right when she was alseep & had a severe flat spot on her right side. Her forehead was uneven, she had a bulge on the left above her ear & her ears were uneven. The tight muscle was on her right, so prevented her from looking left effectively.
Firstly, as ConnorTraceptive pointed out, you need to remedy the Torticollis.
Once it had been brought to my attention I started turning her head while she slept, at first she looked up, very awkwardly but after a week or so she looked more comfortable. Then the physio we saw recc exercises.
I was told to hold her chest to chest facing my right & hold her head firmly for 10 seconds. I had to do this 3x a day for a month. This stretched the left side muscles, she hated it for a couple of days, screaming etc & I felt so cruel. But I noticed improvement very quickly. She was turning her head in her sleep within days! She now had a straighter forehead, no bulge above her ear (although her hair is kind of 'stuck' in that curve now! But it is good, as it shows me how she has improved).
While her plates were moving around her fontenel shrank & grew again & she had a pronounced indent on the left side of her forehead, which has now gone. So it may seem like it is getting worse before it gets better.
The paed said no to a helmet as they come with their own issues (sorry, can't remember what he said)
Now at 8 months she has improved alot! She still has a flat spot, but it is not at all noticable to an outsider. If it doesn't improve anymore she will be OK, and it won't notice under her hair.
So, I hope you are treating the torticollis! As it won't go on it's own. Lots of tummy time, don't leave your ds in car seats for prolonged periods, try to encourage positioning to the other side while sleeping.
Oh & I would advise that you seek profesisonal advice before you try the exercises I did with dd.