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Question: what are my (30 Male) chances  of having contracted an STI from giving and receiving unprotected oral from another male? Should I continue unprotected sex with my wife? Should I get tested for any STIs?

Details:

Around June 6th (4 weeks ago) I received and gave unprotected oral with a man for about 5-10 mins with niether of us finishing. He claims to be disease free and is himself married and hasn't messed around with another guy in 20 years. I thought nothing of the event until around 5-10 days later my testicles or the testicle region started to feel like a dull ache (especially the right side). I noticed it while drying myself off in the shower. I chalked it off to my excessive masturbation (~3-4 times daily) and experimentation with solo prostate play. Eventually I cut back on both and the pain is gone but it left me wondering. This symptom above is the only one I've since experienced. Your input is greatly appreciated. Thank you

In general:

1.  Amongst penetrative sexual encounters, while theoretically any STI might be transmitted through giving or receiving oral sex, biologically, transmission through oral sex is less efficient (and therefore less likely to occur) than rectal or vaginal penetration.

2.  In terms of HIV, there are no instances that we have seen or heard of in which HIV has been proven to have been acquired from receiving oral sex from an untreated HIV infected partner.  There are proven cases of HIV acquired from performing oral sex on an infected partner but the are uncommon, estimated to occur, on average, about once in every 10,000 encounters with an infected partner (i.e. like performing oral sex on an untreated infected partner once daily for more than 27 years).

3.  In terms of acquiring STIs from receiving oral sex, if a partner has oral gonorrhea, the infection may be transmitted if they perform oral sex on you.  Occasionally recipients of oral sex can acquired non-chlamydial NGU from the introduction of a partner's non-STI oral bacteria in the urethra but this problem is typically self-limited and not a threat to partners.  Chlamydia from receipt of oral sex is rather rare and herpes type-2 is almost never acquired from receipt of oral sex.

4.  In performing oral sex on an infected partner there is a measurable risk of acquiring gonorrhea of the throat.  The risk of other STIs is far lower.

Your situation:

Your partner sounds to be relatively low risk (most persons tell the truth) and if you were going to develop a symptomatic STI, it would not take 4 weeks to occur.  The testicular discomfort you describe is the sort of symptoms our clients sometimes get as they start to watch themselves for STIs following a somewhat concerning encounter.  it does not sound like an STI- STI related testicular discomfort would not have resolved and does not come and go. I suspect the alternative explanations you suggest are more likely.

I hope this perspective is helpful.  With regarding to your recent concerns, I would not worry.  EWH