I don't know about weird but that's a bit sad read. I hope you're young.

Please put an NSFW tag on this. I was on the train and when I saw this I had to start furiously masterbating. Everyone else gave me strange looks and were saying things like “what the fuck” and “call the police”. I dropped my phone and everyone around me saw this image. Now there is a whole train of men masterbating together at this one image. This is all your fault, you could have prevented this if you had just tagged this post NSFW.

If you're about 14-17 or a bit more or less, this is perfectly normal. Should become more rare once you get older. Just rummage in your backpack and casually place it onto your lap. Problem solved.

Boners are largely age dependent. I remember in high school I got random boners all the time and anything could trigger them. Now, at 40, I have way more control plus novelty matures and wears off IMO.

You should have said hello or tried – YOLO. Those opportunities dwindle with age for the most part.

Try to step out of your own perspective in a mental abstracted exercise and ask yourself, 'If that was me is there any chance I would be touching someone like this and not notice?' Then, 'What is the least amount of meaning I would attribute to such a gesture? – (now conservatively divide that by /10).' Finally, 'If I were in this person's state of mind, how would I perceive a stranger talking to me?' IMO, when with a friend, the person is going to be on the high ground and feeling secure and safe from embarrassment. If you directly address the touching, you're going to be at a disadvantage and get shut down. However, if you can find a way into making conversation, the touching was like an invitation to do so. By not addressing it directly you are using it as a step up into exploring more. The hard part is just the small talk. Many people are just more tactile, but in our present world, touching strangers (at least in the USA) is very rare.

Natural reaction.

Natural reaction, but also it is good that you weren't trying to be a creep in that situation.

Na. Without context maybe but from your account naaaa I used to pop a chub on the school bus going up and down the country roads. Usually just played it off as scratching my balls but would actually just tuck it into the waste band.

No matter how many people say otherwise the only thing that truly matters at the end of life is your happiness and psychological well being. Family, friends, jobs and houses will come and go. Don't ever let yourself get too lost being comfortable with depression. It's not ever going to get easier but the rest of life will and does get easier. Especially if you continue to fight the depression because nothing in life will ever be more taxing than fighting yourself.

Boners are a natural reaction that's pretty much out of our control so getting one and hiding it isn't a bad thing.

It's not okay nonconsensually involve someone in your stuff so making someone aware of your boner is absolutely not okay. Ditto for taking advantage of a situation like that to grope/fondle the person.

I'd need to know more to be sure (and to know specifically information you don't know) but it doesn't sound like you did anything to make anyone feel uncomfortable so I think there's nothing wrong on that count.

It does sound like you're extremely tightly wound sexually though, so there may be some stuff you should examine internally - like why that was so exciting for you. It sounds like you may need a more healthy sexual outlet if you're reacting this strongly.

I mean, your reaction was nothing but a physical response, so I wouldn't say so.
As long as you don't do it on purpose, no, not weird.

Pro tip: Flexing leg and feet muscles can cause the body to steal back that blood flow and cause things to settle down.

That said, there's an art to doing that without looking like you're doing something weird. Only you know what's too weird for you, and then aim not to go past half way to that, just in case. Subtlety is key, and when you think you're being subtle, you probably still need to dial it back a notch.

Mental arithmetic or something else unrelated to the situation that moves blood flow to the main brain can also work. Silent brain games on your phone. Sudoku maybe.

Good luck.

But she didnt stop leaning on me, this went on for the next 10 mins.

You could kindly offer her to sit on your lap.