Hi,
Welcome to ehealthforum.
The altered vaginal discharge is usually associated with vaginal infection. If no other symptoms of infection (like itching, foul smell etc) are associated, then chances of pregnancy are a possibility. Condoms are known to have failures. Pullout/withdrawal method of contraception is associated with highest failures (it is known to contain sperms and no man can be 100% sure that pre-cum/ pre-ejaculatory fluid did not leak out during vaginal penetration). Wait and watch for your periods. Look out for development of any other new symptoms if pregnancy is suspected. If periods do not start within 10 days of expected period dates, or if you get abnormal periods, or if you suspect chances of pregnancy, consider visiting your doctor/gynecologist at the earliest for thorough examination (to confirm pregnancy related changes/signs in body) and blood/serum HCG level test (to confirm/rule out pregnancy accurately). If pregnancy gets ruled out, and if you are not ready for pregnancy, but intend to remain sexually active, you should consider visiting your gynecologist to get started on suitable regular birth control measures to be protected (after your periods). Be regular with birth control use as instructed. Avoid having unprotected sexual contact. Be in regular monitoring and follow-up with your treating doctor/gynecologist and report any new/abnormal symptoms immediately. Drink plenty of water. Take adequate rest. Maintain healthy diet and lifestyle.
Take care.