Can you get hiv from giving a blowjob and getting a little bit of precum in your mouth?

Many things possible: But rare things are rare, so no worries. For example, one can even theoretically get HIV via deep kissing, but it's also probably super rare. If both partners have some cracks or scrapes on the lips or inside the mouth, or any bleeding gums, then HIV can be passed. Though rare, possibility of catching HIV may increase with the amount of time spent kissing or doing oral sex with an infected person.