Discharge smells off 😕

Okay so for the past two days I’ve noticed my discharge has been starting to smell a lil funky but not to extreme. So today I noticed it gotten a little more harsh. And it smells kinda like blood like or iron? But there’s no blood. I’m supposed to get my period soon because my breasts were really tender for the past two days as well. But it’s getting me really worried because I did just had sex for the second time after loosing my virginity (to my bf of course) four days ago. But I did use protection! Any advice will help thank you 😅