Yes, that might be a possibility. So with the pelvis you have the two bones as you describe, on either side of the crevasse of your butt. However, the tailbone falls down between these. So if it fractured and healed at an angle, you may be perceiving the pelvis to be at an odd angle, when it may be the tailbone.
Until someone in the know can palpate, or you get an X-ray, it's difficult to know for sure.