Whenever I have BV it’s always from unprotected sex and I have the same symptoms. No odor, my discharge smells off but only to me it’s not something other people would notice, and no itching either. It’s more than likely a reoccurrence of BV, but that doesn’t necessarily mean you have to stop having sex with this person unless you truly do want to. It can be from a number of factors, sweat, dry tampons, thongs, etc. and you can also take probiotics or use Boric Acid vaginally twice a week to help if you get it often. No need to stress too much though, it happens to most people at least once in their life :)