is redness, soreness and sensitivity of the skin normal after using a home remedy of baking soda an lemon?

I have been trying to lighten the skin on my knees (i am olive skinned). Home remedies suggested a body brush, lemon and baking soda/water paste to be applied and left for 5--10 min then rinsed off. I have done this, however my knees are now red, sore and a bit warm to touch. I have applied some Fucicort Creamto the area to calm it down and iced the are as well. But i am worried! Is this reaction normal??? Have i burnt myself?! will the area get darker now?! What should i do now? Please help!

No doctor answers yet