Tripped and hit my knee, now have a small bump, filled with fluid in my knee. Anyone else experience this?

I know, I know:Go to the doctor!!! and I will this in a couple of days, but for now I'm just trying to deal with curiousity.

It's been about 3 days since in hit it on pavement and It only hurts when I lean on it. I'm just a bit concerned, bc I'd like not to have to chop a leg off for a silly trip. I know it's a long shot, but have any one you ever experienced something like this.

23f diabetic for 20 years.

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