Should I be worried that she didn't message me back?

[James]

I did some little flirting with her on facebook for like a week (I liked her new profile picture, we had a poke war, commenting random google images on her wall for like an hour lol, etc) and then Monday she poked me, and I poked her back, but now she hasn't poked me again since the (she's usually almost never on during the school week though, last week was weird). I wanted to ask her to hang out this weekend sometime, so then two days ago (Thursday) I saw her on and I said "hey loser" to her on chat, but she didn't reply and it turns out she didn't even see it until last night (Friday). Should I worry that she didn't message me back? I mean I wouldn't message someone back a day late if they just said "hey," so I don't think so. And should I try messaging her again tonight or should I wait a day or two longer?
Thanks
PS I know that just because I flirted a bit with her doesn't make her mine for the taking, but it just seemed weird that she abruptly stopped all contact. And I know that this should be a pretty insignificant thing to worry about, but I just really like her, I guess.

Oh yeah and a few weeks ago something similar happened where I sent her something and she didn't reply and then that time she replied 5 days later. Although that actually had something to say, it wasn't just "hey" (I sent her a picture of a turtle and told her it looked like her...she seemed to think it was really funny). That was the first time I really flirted with her and I was encouraged by her response then and afterwards. I just feel like I've messed something up. I'm not exactly experienced with this kind of thing.

[Aj]

you shouldn't worry, people get busy, that's all there is to it.

[lisa]

I think Facebook chat is pretty unreliable. Sometimes it can say someone is online when they're not, or maybe someone is actually using her computer. Since she's not on during the week it could be she simply did not see your message. Try to get a phone number to see if you can text her. Granted, not the best sign that she hasn't been on, but you're only in the beginning stages of things and she probably doesn't want to come across like she has no life, or she's leaping to get on the computer to message you. Don't freak out too much...I don't think you did anything wrong and she just does seem to like you. She maybe just busy. It's too early to freak out about a few days of no contact...in the beginning less is more.

[Chris]

wow man you gotta chill, you said yourself that she doesn't get on during the school week, and there isn't much of a response to hey loser, but why are you keeping it to facebook if you like her so much. Hell man, text, call, or even just grow some and go up to her and ask her if she wants to do something this weekend. You all have been talking for about a month, regardless of whether she sees it romantic or not, you atleast are into the gray area where you can see if she wants to hang out as friends and see a movie or something, and just let it either blossom or stay where it's at from there. Either way, good luck, i hope it works out for you

[Shelly]

Ok, like guys, girls also need their space. Girls are complicated in the way that they can be really in to some one one minute, and then want to have anything to do with them the next, (I think it's just part of our hormone processes). If I were you I would just keep a bit of distance from her for little while, let her come to you, trust me, us girls love moments of intense interaction and then we need a break for a while. If she's in to you (and it sounds like she does) she'll text you back soon, or talk to you soon, but for now just keep it low key, and relaxed - it's a way of showing that you understand and respect her space

[C]

Don't stress out about it- sometimes we just can't think of a good response, or feel like we're replying or talking to a certain person too much. We then start to worry about this, and instantly halt all communication. As far as I've experienced, I can't keep it up for long- she'll get back to you soon enough. We start to over interpret everything we start saying at one point or another, from the time it takes you to respond, to who texts who first, to how much we respond, etc. Like I said before, don't sweat it. It's completely normal. Plus, you two seem to already have a rapport established.