Hi
Welcome to the MedHelp forum!
All I can suspect is some STD or bacterial vaginosis. Go to any STD clinic and both you and your partner need to be tested. Look around for lesser costing options or free ones. Yellow vaginal discharge is seen in cervicits (inflammation of cervix), vulvovaginitis (inflammation of vulva and vagina) and STDs like gonorrhea and chlamydia. Cervicitis is not a STD and may not cause any symptom. STDs like gonorrhea and Chlamydia (also known as silent disease) too may present late. All these can cause irregular periods as well. The discharge can also become yellow due to medicines and also it could be a normal finding. If it is a STD, you can pass it to your partner. Greenish discharge is usually due to bacterial vaginosis or due to trchimoniasis.
I am sorry but this is something that cannot be diagnosed or treated on net. I can just provide some idea. Take care!
stop having sex your just passing it back and forth and there are clinics you can go to and get tested could be simple has a bad yeast infection or it could be an std go to the clinic
u need to get tested that not good sounds like std to me but hope thats not what is is its should be places were u can go in get tested for free