Horrible vaginal smell, PLEASE HELP?

For the past day or two, I have noticed an awful smell in my vagina. It is not itchy, it doesn't burn, nothing FEELS wrong, but it is just this awful smell. A couple of days or maybe a week before this, I had lost my pack of birth control and missed 3 days of pills. I bleed very badly and during that time I wore scented tampons because that is all I had. I took two pills for three days to get back on schedule and since I have stopped bleeding a couple days ago, this smell has taken its place. I don't think it's fishy, it is more like rotten. I used a cotton swab to see if there was any discharge and when I pulled it out there was a light orange/red/brown (i couldn't really tell what color) and it smelled TERRIBLE. Almost rotten, like something dead or something. Does anyone know what could possibly be wrong? Am I always going to smell like this? I have an appointment with my OB/GYN in a couple days but I just need something to put my mind at rest. I read that some people have gone to the ob/gyn and there was nothing to help it. I have also had unprotected sex with my boyfriend and he did get off in me. Could that be it?