Even though this is a forum
in Spanish language, I will answer your question
in English. We have other forums
in English.
There is no risk of HIV infection at all from receiving oral sex. In many years of clincial experience in this field, I have never come across a single case. The reason for this is possibly because the saliva neutralises the virus, even in the case that the other person was positive with bleeding mouth sores, which does not seem to be the case here.