Slipped on the stairs & fell 2.5 weeks ago. landed on the small of my back on the edge of the step. iced it. spine felt fine. bruising going away. still a good size lump -very tender. no other health issues. no meds. should i wait or seek med care?

If you have a large,tender lump after 2 1/2 weeks, I recommend seeing a physician for evaluation and advice. A bone bruise with a hematoma ( blood clot) would be a likely cause if your ongoing symptoms. Sometimes a persistently tender hematoma has to be excised through a small incision. In the meantime applying warm compresses several times daily may help it dissolve.