What Causes My Eye To Repeatedly Turn Black And The Tingling In My Cheek Weeks After A Fall, Despite A Clear CT Scan?

I took a fall down the steps several weeks ago. When falling I hit my face on a board. I did get a black eye from this fall. It has been over six weeks ago and now about every other week my eye turns black again. I have a tingling feeling in my cheek under my eye. I went and had a catscan and they said that nothing was broken. What could be causing my eye to still turn black every now and then?