Delayed wound healing - Red patch skin.

A month ago, i got knee got an abrasion by bike accident, above patella, there are 2 places where the skin scraped off, & the hypodermic layers were exposed. I got Tetanus toxoid vaccine, took proper course of antibiotics. (Antibiotics i took for a month are: 1. "Amoxyclav625-7days BD", 2. "Ceftum-10days BD", 3. "Amoxyclav625-10days TDS" with Clindamycin300-5days BD Alongwith, Chymoral forte TDS for 12days After the wound got covered by bandage on the day of injury, i kept going for work, & no discomfort till week was over. And now the wound started to itch, ache and i left wound open. Got drenched in rain 1-2 times. the skin around the wound started swelling up forming bubbles (containing red fluid), the wound was at 2 sites above patella, but the patch started growing exponentially, with bubbly appearance 5x times the size of actual wound site. After 1month, after i stopped antibiotics completing courses, & dry patch skin fell off. Leaving dull red-pink beneath new skin