Why don't guys respond to their text messages sometimes? I get really worried when he doesnt.

I usually don't keep my phone on me.

some people, like me, usually don't respond to messages such as how are you...right away, it makes you seem to needy, and that's not attractive, I usually respond to messages such as those when I have time, but if its an emergency and I'm talking house is on fire type thing, then ill respond right away

so he's just trying to look like he's not needy

It's possible they don't like texting, or maybe they just aren't that interested in you. Or, they are busy.

Woah woah woah, don't go all text crazy on this guy. A lot of guys feel like they don't need to respond to text messages right away, and they sure as hell don't like get bombarded by them. Just don't text him, until he text you back, and then don't text him for at least an hour. Gotta have some self control girl!

you have no idea how many girls sometimes over react when guys don't text back. Maybe he doesn't have a texting plan. Maybe he doesn't like texting. Maybe he doesn't have his phone with him a lot. There could be tons of reasons he's not texting you back. Don't worry too much if he doesn't text you back. Just brush it off your shoulder and don't get too hung up on him.