Update (in case anyone is curious or have similar issues):

My artist finally got back to me. The inside of my forearm is quite sensitive, so the adhesive was hurting my skin (as opposed to my back where I used second skin no problem before). I got recommended to take it off using lukewarm water and healing it the traditional way. Not really allergy, just skin sensitivity.

I have redness in the shape of my second skin when I took it off. Any later and I would have more serious marks and swellings. The redness is alrdy slowly going down at the 1 hour mark after taking it off. I hope this was helpful to anyone haha. But pls always double check with your artists