AITA, recently confessed feelings to my crush, which were reciprocated with her being open to exploring. Now it's been 3 days without hearing from her. Am I expecting too much?

Sorry in advance for the long post!

I (19M), met a girl (18F) on a penpal app around a year ago, from which we swapped Instagram usernames and started chatting on there.

We were exchanging fairly long penpal type messages, but after a while I got the impression that she was rather self-centered, that coupled with the fact that we didn’t have many common interests led to a point where I was taking a pretty long time to respond (anywhere from 1-4 weeks at times), although I would still put a fair amount of time into my replies when I eventually got around to them.

Over the months I warmed up to her, and started to realise that actually, what I originally took to be self-centered, was likely just the culture difference (she comes from a rather well-off upper class background, which is something that I’ve never been able to identify with), and she was a very genuine and sweet person after getting to know her more.

I was still pretty poor at responding by this point, as life had managed to get in the way, but in June I started to feel pretty guilty about always leaving her hanging, so I suggested that we ditched the whole penpal thing and started being more traditional friends, something which she said she had been thinking too (the intention of this was to switch to shorter but more frequent texts).

The conversation was flowing pretty well so we slipped back into the whole multi-paragraph long replies, although I made the effort to respond as soon as I could anyway, despite it definitely being overwhelming at times. It was around this time that she made a few comments that I took to be her flirting with me, which made me see her in a different light. I returned the flirting, and at times it definitely seemed a bit awkward, but she responded well as a whole and kept doing the same back.

By this point I was starting to develop more romantic feelings for her, but noticed that while I was responding anywhere from an hour or two later, she typically only sent two or three replies a day, that later went down to one, shifting to one every other day, and you get the idea.

She said she had some family stuff going on which I said was alright, but I felt pretty let down as I was crushing over her quite hard at one point, however I figured if she was interested in me she would’ve said so more concretely or at the very least been responding more often, so when she did occasionally reply, I switched back to the older penpal dynamic and just tried to get any feelings beyond that out of my head.

Fast forward to earlier this week, and she had sent one of our usual sort of texts, but then a day later double-texted me with a picture of something that had come up in conversation and said “saw this and it reminded me of you” which I thought was sweet of her to remember I had mentioned it.

I responded to that pretty quickly and from there everything started to click again, and we shifted to the sort of friendship dynamic that I was hoping for a couple months back.

Curiosity got the better of me however, and I said that it had been playing on my mind and asked if she was indeed flirting with me the other month, or if I had gotten the wrong impression. She admitted that she was, but found relationships/flirting very awkward so was never too sure what to say or how to act.

From there we had a heart-to-heart about feelings and stuff, from which I told her that yeah I felt a connection there and if she was open to it, would definitely like to see where things go. She said she liked me too and wanted to go into things with no pressure/expectations, start slowly and just see how it developed and if friendship did become something more, which I agreed with as I never thought we’d jump into more than that off the bat anyways.

It's been 3 days now since we had that conversation, and nothing. It’s not out of the blue at all for her to go that long or longer without responding and I haven’t been blocked or anything, so she’s not 'ghosted' me, but I just thought things would be different you know? The last thing I thought from that conversation and the dynamic change was that she wouldn’t text at all for 3 days.

I mean I’m not jaded or anything, I totally get that she had other stuff going on and I’d also be hypocritical to expect her to respond ASAP as once upon a time it was me being the awful at replying one, but I just can’t help but thinking if this is how things are getting started, then it doesn’t exactly give confidence for anything else. Plus I’d have less expectations of a penpal or acquaintance than I would of a friend or potential love interest.

Some extra info: We are in the same country, not close enough to have met already, but not far enough to rule that out in the near future, and we had already discussed wanting to meet as friends at some point. We have never called or done anything other than texting, but it’s something we both mentioned in the past, just never materialized.

I guess what I’m trying to ask is; Am I overreacting? Am I asking too much? Should I cut my losses? How best should I bring everything up? Is it worth pursuing?

Will try and respond with any extra info that's needed, thanks so much for reading!