Helpppppp

So... Basically I'm a virgin, nothing has been down by my vagina not even fingers.. And for about a few months now my vagina has always had a foul smell. I wash it regularly in the shower and it still has this gross smelly smell.. I'm 18 and the reason why I mentioned nothing has been near my vagina is because I knew the first thing people would comment was that it's an infection of some sexual transmitted sort but it just can't be. How can I get rid of this and why does it smell so bad?? I've tried everything ..