Getting a bad smell before and during period?

So recently for the past few menstruation cycles, I have noticed my down there getting a bit of a different smell about a week before my period, and then during my period. I know it's normal to get some sort of odor, but it is different to what it usually is. I wash all the tine, and even after every time I pee, I use water to wash it, but the smell doesn't seem to go. Unlike people that report smelling more fishy, mine is completely different. It is extremely hard to explain. But it just doesn't smell right? And everytime I start my period, the blood comes out really dark and brown, so I am guessing it is old blood? It is not a rotting smell, and it is not musky either. However it doesn't smell like sweat. I want to say metallic, but it is not that either. When I am off my cycle or not within the one week before it is due, I don't get the smell. I am extremely self conscious about it. I will be going to see my boyfriend in a few months, and he has a vey high sexual drive. Period sex doesn't scare him either. But this smell just doesn't smell pleasant either. But it doesn't smell like the explanations for any type of bv. Can you please help? Is this normal? Why is it happening? What can I use to help?

Getting a bad smell before and during period?
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