YOU SAID:

My buttocks yre in generous amount of pain

INTO JAPANESE

私のお尻はかなりの量の痛みに悩まされています

BACK INTO ENGLISH

my butt is suffering from a fair amount of pain

INTO JAPANESE

私のお尻はかなりの痛みに苦しんでいます

BACK INTO ENGLISH

my butt is in a lot of pain

INTO JAPANESE

お尻がすごく痛い

BACK INTO ENGLISH

my butt hurts so much

INTO JAPANESE

お尻がとても痛い

BACK INTO ENGLISH

my butt hurts so much