前几天我晒伤了，现在我开始脱皮了。 哎呀，我XX脱皮了！ you can substitute XX with different body parts such as 哎呀，我手臂上脱皮了 or 哎呀，我脚上脱皮了 or 哎呀，我脸上脱皮了. Or you can say 哎呀，我手臂上在脱皮/哎呀，我脚上在脱皮/哎呀，我脸上在脱皮 and the sentence "Damn it, I'm peeling" can be literally translated as “哎呀，我(身上)在脱皮” 蜕皮 is usually used to describe some insects exuviating or a snake casting off its skin

蜕=虫+兑 Given that 虫 means worm, so 蜕皮 is used to describe snake. 脱=肉+兑 月 in 脱 is actually a simplified form of 肉, hence human 脱皮. 我几天前被晒伤了，现在开始脱皮了。（A few days ago I got sunburn, now I'm starting to peel). 哎呀，我正在脱皮。(Damn it, I'm peeling.)正在+doing=be doing

前几天我被晒伤了，现在开始脱皮了。 哎呀，我脸上/胳膊上/腿上脱皮了。 蜕皮一般是节肢动物和爬行动物。 如果你被晒伤了，可以试试用 牛奶和蜂蜜做面膜，涂在脸上。我的朋友上个星期也被晒伤了，她用牛奶和蜂蜜做面膜，很快就好了。

几天前，我晒伤了，现在开始蜕皮了。（Delete 被） it is also correct. 几天前，我晒伤了，现在开始掉皮了。 Change 蜕皮 into 掉皮， using in oral Chinese. Generally speaking, 蜕皮 is described in snakes or worms mostly ,with meaning of "mult". Surely it could be used in human being, but that is in case of seriously. 我的皮蜕下来了。This will give us imagination all fur is peering.

Peel is used when you get the skin aparted from some fruits and vegetables.