I Fell 8 Days Ago, Playing With My 9 Year

I fell 8 days ago, playing with my 9 year old and tripped over his feet landing like a sack of potatoes on a concrete pavement, 2 badly grazed knees and hands, bruises on both legs and wrists but 8 days on I still have a weird numb sensation below my left knee which took 90% of the impact, any idea why? Also this leg isn't sore as in bone sore but I can't kneel on it or even brush past something without it causing me a huge amount of pain