I agree with the second post. Sounds like BV. Go to the doctor, ask for a culture and they can give you antibiodics to clear it up.
Also, request the gel if you do have it. Do not take clindamycin or any other harsh antibiodics, they can cause C-diff and other bowel problems.
Sounds like you have Bacteria Vaginosis. Its no considered an Std, and its not apart of the doctors routine check, you have to ask to be tested for BV. Its treated with a few antibodies.