Is Damage To The Sciatic Nerve Causing Buttocks Pain After Falling?

I fell backwards from a height of about two feet fell on my back and landing my buttocks onto a hard object.. about 4 weeks ago. I had bruise approx. 9 x 6 in middle of my butocks in about 6 hours. The applied some hirudoid ointment - an ointment which helps to break down the bruising and not allow blot clots. The initial throbbing pain stopped and bruising gradually over course of few days disappeared. I still am experiencing pain occasionally in the same area if I am seated for any length of time. I am not feeling any pain while walking. Could the sciatic nerve be the issue or something else. What happened