I Hit My Right Knee Really Hard Today On A

I hit my right knee really hard today on a cement planter. The impact was intense as I didn't even see it. I'm 61 yrs old, very active female, overweight about thirty pounds but my knee is extremely swollen and so what painful and cramping on my upper calf. I usually walk 3-5 miles per day. I'm taking ibuprofen and icing it. I have had previous knee injuries, torn meniscus and arthroscopic surgery.