Charging Biochar skin rash

Hi I was charging a Biochar Bag from a local nursery it was Mixed with peat moss and some other stuff. I added chicken manure to the Biochar/peat moss bag and Added tomato tone to 3 paint buckets filled with the compost Biochar mix and 1 bucket was a worm compost bag with chicken manure. I had pants on, but they were pretty thin. I was stirring it at night to try and keep it aerated, and some may have spilled on my knees while I was kneeling and stirring. My knees and parts of my legs got weirdly red. I will ask a dermatologist, but I am wondering if I did something wrong with the Biochar charging. Thanks