Would you think he cheated?

Am I being delusional??

I haven’t seen my boyfriend in over 3 weeks as he was traveling. I seen him last night, I was giving him oral when I noticed a weird smell. It wasn’t a bad smell, just not his regular smell down there-kind of like how his penis smells like my vagina after we have sex but not my scent. I didn’t say anything but it was just off to me. We have unprotected sex all the time so I’m hoping not. I’m going to take a test soon. I know I sound a little crazy but I’ve been with him for years and this is a first time I’m experiencing this.