Some folks cant process this stuff well. My wife is also one of them. She gets a rash from it every time even at 1mg dose. Rash lasts about 2-3 days and she does say the area burns and is clearly inflamed. Same solution works fine for me and she is fine with other peptides and glp1s.
Another possibility is your BAC water. Too much alcohol will burn though not all day... not in my experience. I made some spicy BAC water in the past but its like a few minutes of burn at most.
Another is your compound is crap. Did you get it tested or are you relying on toilet paper COA by the seller? Those are worthless coming from a UGL. Literally worthless. You can assume they dont exist. Either test it or prepare for pain.
As for GHK-Cu, I did tons of research a month or two ago including reading the clinical trials. Most are trash. The only things I got out of them is surface level wound healing and collagen building (the two are not excluse per se). The latter has plenty of anecdotal account showing it works when microneedled. Not the same as injection but in theory, it should work within its half life.
The current reality is the peptide is overhyped thanks to influencers and retarded kiddie looksmaxers desperate for attention and sex, and it bled over to reddit where it hit less intelligent adultsand now people expect the moon. It absolutely will not remove wrinkles or scars. Not on its own. It cant do that because thats now how our skin works. To do those things you need to reset your collagen layer by damaging or melting it 1st. Then it can act as support at best. But without that, it wont do much which is what the trials showed. If you are older and have thin skin, it *might* help you a little to thicken it. This is beneficial but by how much? No idea. I wouldnt rely on it.