I recently found out a good friend of mine had a small cock, it doesn’t bother me and I only reacted by laughing as he’d previously told me that his dick was big, but it hasn’t changed any dynamic in our friendship
I can quite understand part of this, and I say that as a guy with a small dick myself (2-2.5" soft, 4.8-5.2" hard, and thin). I've had 2 experiences of finding out close friends had tiny dicks, in one case very unexpectedly - which I'll share in detail here too soon.
But in spite of the fact I've been on the receiving end of the mockery and know how humiliating it can feel, in both cases I reacted the same way you did - laughing right in front of them - bc they also made the same mistake of claiming to be big.
One was an Asian friend who unfortunately fulfilled the stereotype of a tiny Asian dick but tried to claim one night in front of our friends he was "big, and not just for an Asian." Long story short i talked him into a private size comparison contest in the men's room and took great delight from much outsizing him (aided by a 3-3.5" softish semi from the arousal of what was happening

) and making fun bc he was actually so tiny (1.5-2" soft max and thin, buried in a massive bush of pubes).
Certainly not my best moment as a friend by a long shot, but I couldn't resist making some jokes about just how tiny it was, I couldn't believe he actually agreed to compare, and he should be too embarrassed to show it to another man. It definitely did change things bc he was obviously very humiliated by it and colder to me after that (sadly bc the truth was I found him hot and actually got turned on by his tiny penis!).
The other guy was a tall, hot, athletic jock who'd had plenty of fun joining in with mocking me over my dick size after it got spread around by another jock friend who'd seen it. I got a clear, direct view of his at a bank of urinals facing in at each other at a festival. He was 1.5-2" max too, bit thicker than my Asian friend but still below average, and also made worse by a big bush that buried it more. I was so shocked I couldn't help but stare with a massive smirk across my face. He saw this and was visibly embarrassed, finished up and tucked it away ASAP.
After that he never made fun of me anymore and I always got a kick out of giving him a smug grin anytime he'd be playing at "alpha jock" and bragging about his size in front of other guys and girls he fancied, seeing his discomfort that I knew the truth and could out him for it anytime i wanted to.
Ngl - I totally got a lot of satisfaction (sexual and in general male ego) from laughing at my Asian friend's tiny dick and seeing his reaction to my own (underwhelming) penis size compared to his after his futile brag. That definitely had a lot to do with enjoying the feeling of being the bigger man for once though. But I did and still do feel a bit guilty for how it affected him and our friendship.
On the other hand, tbh I absolutely fucking loved finding out that my jock friend had such a pathetic little dick for a guy like him and I totally got off on the power of so openly chuckling at it to his face!

He clearly got a kick out of making me feel small and emasculated in front of other guys about the size of mine, so when I found out he had an even smaller dick than I do, it was extremely enjoyable.
If he hadn't acted the way he did towards me then even though I'd still have smirked at seeing such a small cock on such a masculine man, I probably wouldn't have played on it after that. I loved the fact that he was so sexually inadequate in the dick department, but i loved it even more that he knew i now knew too and I could make him feel so insecure and worried about it.
That was a way longer answer than I was planning to write!

But I guess the main point is that yes, I've found out male friends had small dicks; I did - rightly or wrongly - laugh at them for it, and in the case of my Asian friend outright make jokes about what a tiny penis he had and how he shouldn't be letting other guys see it; and that it definitely changed the relationships in both cases. But likewise, when male friends found out i had a little dick it almost always changed things in the same way too. I actually find small cocks hot but the competitive male ego in me still gets off on establishing a dick size hierarchy.
Final point for all the hung guys on here (which is 95% on lpsg!): for most us guys with small penises, it's a constant source of embarrassment and shame, and when guys like you find out about it, it almost doesn't matter how you react bc generally we never stop thinking about how now you know what the size of our dicks are whenever we're around you


