I wrecked on my mountain bike a week ago. Did it hurt? Not at the time. Did it hurt an hour later? Oh my stars did it hurt an hour later. I went over the handlebars, slapped the right knee cap (and good), bruised the left side from hip to foot, and trophied myself with an honorary elbow scrape.
Exhibit A: Elbow Scrape
A friend of mine gave me the get-yourself-some-abrasion-covers-and-get-them-fast lecture. I said, wah-wah-wah-wah for a day, then conceded, because I didn't have any laying around and they're somewhat hard to find. So I put in some healing Effort and traipsed about town looking for Abrasion Covers.
Exhibit B: AbrasionCovers
I kept the wound covered for about six days. Look at the wound after six days. Magic, yes? Magic!
Exhibit C: Six Days Later.
Now if only someone could provide me with some similar magic for my knee. Frownie face.