Weird Discharge

So my discharge has been kinda funky lately. Usually around the time my period starts, I get this weird odor that smells sour and it is very noticeable (only when I’m starting my period).My underwear are usually soaked when I take them off and my discharge comes out looking like boogers?? Weird way to say it but it’s true. I’m very hygienic and I make sure to wash after using the bathroom and after work outs. I’m not sexually active and I have no idea why this is happening. Any ideas????