Was I wrong here?

I need an outsider's opinion here.

For a little over a week, I've been texting a girl I met through a social media page and we really hit it off. We expressed a serious interest in each other, but had not had the opportunity to meet in person since she had surgery this week. Keep in mind, we have yet to actually meet in the flesh.

Yesterday, I commented on another woman's post on this social media page. She was a fellow ren faire performer, and I wanted to reach out. It was simply a social comment about faires. Think something along the lines of "I'd love to know who did your costume." Well, she saw it, texted me a full paragraph on how she thought we were going somewhere serious, and didn't think we should go any further than we were now if I was talking to other girls.

This gave me insanely jealous vibes, so I simply apologized, expressed that I was sorry if I hurt her feelings, but at no point in our conversations did she communicate she wanted any form of exclusivity. Personally, I thought it was way too soon for that kind of thing. We only knew each other for a little more than a week. Did I actually do something wrong here, or was this a complete overreaction?

I ask because dating has always been hard for me, and I've often gone years between relationships. Was I really in the wrong?