The STIs that can be passed when you receive oral sex are Gonorrhea, Chlamydia, Syphilis, Herpes and HPV. If the person giving you oral sex has any of these they can be easily passed to you.
Testing is the only way to know for sure if you have been infected so please check out our Find a clinic section for a testing clinic in your area. You may also want to look at our STIs at a glance chart on our Types of STIs page to see when it would be best to test. A good rule of thumb is to test if you notice any symptoms or three months after a risk.
It is good that you have had the red bumps check by your doctor. If they are only visible when you are erect then they are not related to any STI.
Please leave a comment to let us know if this answers your question or if you need more information.
Health Nurse
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