I hit my knee pretty hard. checked with a doctor and there was no fracture but now its a bit numb and squishy? what could it be?

Knee strain, bruise: squish sounds like local swelling. you damaged tissues around the knee, tendon, ligament, and muscle.. ice helps, either by ice pak or ice massage. and anti inflammatories, like ibuprofen and naproxyn. these are generally self limiting but if this lasts more than a couple weeks you should return to your doc or see an orthopoedist to check for internal injuries