Actually, I didn't find it very Seinfeldian. Maybe a little in the first scene with Ethan's unashamed sexism. I really like the scene with the two girls talking, and you found your own flavor and rhythm that was much more like romantic comedy dialogue than anything else. (And girls talking in Scottish accents is incredibly cute, for my taste, but maybe that's because I was raised watching movies like "Gregory's Girl" and "Local Hero.") You have some very nice looking shots in the film as well.
A few issues. Firstly, your film's called "The Text Message," but we see a phone screen only once; seems like a big oversight. I would have liked to see text messages as framing devices for the scenes, and used in a way that was central to the plot and characters.
Also, when our hero is looking at her phone, is she deleting Ethan's contact? Because the shot cuts off and you can't really tell. So Martin's supposed to be Ethan under a different name? It wasn't quite clear enough, especially as she describes Martin like she's seen his picture -- so if Ethan gave her a fake pic, then we need to understand that.
But nicely made, otherwise.