is it ok to go down on my s/o and make love after?

I have never went down on anyone and my husband will be my first. I know this might sound stupid but if I go down on him and my saliva and everything has been around his penis then we make love will I get an infection or something or germs on my vagina? I do want to suck his penis as much as he  wants me to but I get worried about those little stupid stuff.