YOU SAID:

but now ive got a bellyache

INTO JAPANESE

しかし、今私は腹痛になった

BACK INTO ENGLISH

But now I got a stomachache

INTO JAPANESE

でも今、腹痛がした

BACK INTO ENGLISH

But now I have a stomachache

INTO JAPANESE

しかし、今私は腹痛を持っています

BACK INTO ENGLISH

But now I have a stomachache