Menatlly overwhelmed by a past sexual experience

[TerrifiedInLA]

First off, thank you all so much for all you do - your service is not only noble but extremely necessary in continuing to educate people about STDs / HIV, etc.

My situation / recent "realization" has brought on a ton of stress in my life and due to this I can't tell if I'm suffering from true symptoms or if its all stress induced.

A few years ago, I engaged in a sexual situation with a friend (we're both gay) I consider to be a very smart person.  Before and since this situation, I consider myself to be an extremely careful person when it comes to knowing how to avoid "risky" behavior.  Or so I thought.

The night my friend and I hooked up, one thing led to another and we ended up in bed together.  I never considered sex to be on the menu for the night.  In the heat of things, my friend, without warning or asking, inserted his penis into me very briefly in which I told him to stop.  The entire incident could not have lasted more than a few seconds.  Due to this, and my own ignorance, I ignored the situation and dismissed it as no risk since it was so brief and I put it to an immediate stop.  There was no ejaculation whatsoever but I don't know if there was precum, etc.  I should also mention I know my status was negative prior to this incident as I had been tested a few months prior.

Since this I have been in a committed monogamous relationship in which we do have unprotected sex since I have thought of myself as clean and free of disease and my boyfriend has also tested negative prior to our relationship.

Recently I was feeling under the weather with vague symptoms so I went to Google which kept pointing to HIV in a lot of my searches.  This has scared the **** out of me as there is one, and only one, situation that could have put me at such risk.  Until I did further reading, I really didn't think what happened posed much risk, if any, at all!  Feel like my own stupidity will come at one of the biggest costs I can imagine.

Maybe I'm over-analyzing but I becoming nearly disfunctional!  Although I'm feeling better I still fixate on every little thing that doesn't seem "right" about my health and keep re-playing that incident over and over in my head.

In a panic I confronted my friend who tells me he believes he's "A OK" and that what we did was so minimal I need to get a grip.  However, he didn't specify that he's been tested recently and knows for a fact he's ok so that only has me spiraling further in my anxiety.

So my rather long-winded question to you is, how high of a risk do you think that incident was?  I don't think I could live with myself if I've caused harm to my boyfriend.  I don't know what to do anymore.  I'm mentally crippled by this whole thing (impacting my work, relationship, etc) and don't know what else to do!!

Please help!!

- Scared

[Teak]

Test.