First month took clomid (clomiphene) 50 mg metformin 1000 mg.+opk on cd23.having pinkish mucous discharge on cd 31.what could this be?never had before.

Ovulation?: You may have ovulated on the clomid/metformin combination. You probably need to have a progesterone level checked ASAP to investigate the ovulation possibility. Good luck!

Could be pregnancy: Take a pregnancy test. If you are using a home test, wait at least a week. If you see a doctor, you can get a serum hCG done now. Take care and stay well.