Lol i’m taking the same train but i see where you come from. Should’ve closed before going in.
Well there's another aspect to it, if your taking the same train, maybe you have time, but if she is low interest this is gonna be a really abrasive interaction for her, rather than accompanying her, you may be following her which is a different energy.
The second you find out she's taking the same train, you should run some basic logic in your head and think if you are gonna be taking this route regularly and if she is... If your gonna see her again, you should back right off, especially if she's lukewarm and kind of not feeling you because your gonna see her again.
When cold approaching, you'll know in seconds if she's into you or not which is why introducing levity through comedy is such a great tool to use because it's totally believable that you just wanted to have some fun, your authenticity is still there even if she's not feeling you, then next time you see her, you have another opportunity to be funny... Just cold approaching and looking for it right off the bat, you really have to have your personal life dialed in, not for her to see, but for you to have the utmost confidence in your approach, some guys naturally have that confidence but you sound very unsure of yourself.
Bottom line is that you are absolutely going to fail when cold approaching, it's no different than cold calling in sales, like a 10% acquisition rate on sales when cold calling is Friggin amazing, that means 1/10 calls your making a sale, you can eat off that sometimes but you need confidence, you need a good product (yourself) that is easily able to demonstrate its value and you also need a willing buyer, which is usually predicated upon the first 2 points, confidence and value.
Just taking cold approaches as they come, I mean you can do that as long as your learning, but learning also requires self reflection and that's hard to do under stress, so either get an audio recorder or even better find a way to video yourself so you can observe your own body language during the interaction.