I was in a bike crash, bruised my pelvic area. bruise is gone, but now there is a small lump there. it doesn't hurt and it isn't red. should i worry?

No: Probably tissue swelling or a small reactive lymph node. If it gets red or hurts , then see your doctor about it. Best wishes.

May be hematoma.: After a crash or striking injury, a "puddle" of blood or serous fluid may accumulate in the spaces between the tissues causing a "hematoma" to develop. Sometimes this becomes organized into a gelatin-like mass that may reside under the skin for many months. Occasionally these may even become calcified and remain more permanently. However, with no pain, no redness; probably ok not to worry.