What bit me, could it be a spider, or bee?

I was happily laying out on my patio all day today. As it turned to night, my foot started itching-a LOT. and so I go inside to see what it is, and i see its a bite. So i assume I got bit by a mosquito..but a few minutes later and its this huge white thing, really hard. and more painful than itchy. I put some rubbing alcohol and baking soda, as I heard somewhere that that might help. Then ice..which has helped a lot. But really want to know what gave this to me! Any ideas? I thought maybe a spider or a bee..?