Hi there,
I have been through this type of pain that you describe. Just when I thought I was pain-free, a certain twist or lying down on either side, was sometimes painful &difficult and I thought the same way as you do now. So, I just continued to lay on my back - that is my main position, anyway; and rolling onto my side seemed uncomfortable for several months later. Not painful, but just uncomfortable.
It does seem that it takes awhile for the incision area to become less painful, My surgeon (in my 3-month followup) suggested that I gently massage the incision site whenever I could. Until then, I was afraid to do that - but I began to afterward and that seemed to help a little.
The thing is, there might be discomfort in areas that you though were ok, even 6 months later; I think it takes the rest of your body some time to adjust to the new hip. So, try and be patient, and if it's not a comfortable position for you at this time, wait awhile; eventually it will feel OK as mine does now (9 months post-op).
Take care.