If you are having sex with a new partner or same the odor can increase after sex.. use condoms until you get it treated . Maybe Bacterial Vaginosis
A bacterial infection of the vagina. It is not amenable to home cures; if you have it, you need the doctor to prescribe antibiotics. It is notable for its strong odor.
They will probably put you on an antibiotic. Take a probiotic with it and after like Culturelle to replenish your good bacteria. Sounds like bv.
Tell the ob-gyn you have a bad odor. He or she will look for a lost tampon, and also should swab you for BV. (If he or she does not, ask him to.) If you have BV, get your partner onto the same antibiotic at the same time as you.