girl18

I am 22 year old female. My boyfriend was performing oral sex on me a few nights ago and told me that my vaginal area smelled different. He said it was a much stronger scent and i could tell he didn't like it. I noticed it too. He actually described the taste as "acidy", whatever that means. I asked him if he thinks it smells fishy and he said no. Earlier that same day, I had unbelieveably painful itching down there for a couple hours. Then it just stopped. I haven't had that before. I just started birth control pills and am on my second pack of avianne. I got my period the day after my boyfriend told me this so I was thinking maybe it smelled different because I am getting my period? However, last month (which was the 1st month on bc pills) I didn't have this problem. We have been having sex a lot and sometimes it burns after we are done when I go to the bathroom. Could this have something to do with it? I have had a yeast infection before and I don't think that is what this is. My discharge is not thick like cottage cheese and it doesn't have that bread like smell. What could this be?