AITB for giving "false hope" to a girl I was flirting with?

Throwaway account because friends use reddit.

The title sounds bad, but i'll explain. (Btw i'm on phone and english isn't my first language)

There was this girl on my class (16F) who is really pretty, i (15M) will call her H. We didn't talk much in the beginning due to online classes, she appeared very shy, since she never turned her cam on nor talked on our group chat (where the whole class talked), so, I never really got to know her neither see her really well. One day we ended in the same group for an assignment that obligated us to film a video, that was the first time that I saw her well (the other times were in the exams because school said that we needed to turn our cam on, but H cam was always dark) and when I started liking her, I was always an extroverted person, so, after a bit of interaction and funny jokes in the group, i started flirting with her, and, it appeared it was mutual. Things got better since she entered our private group (with just close friends instead of the whole class) and started interacting with us, it shocked me a little because I didn't expect her to be so funny and talk that much. The whole group noticed we were pretty "close" and even started calling us a couple and stuff, we always "played along", there were even times were I said, jokingly, that I would propose to her in a restaurant so we would get some free desert. We talked about going on dates once we can again, and I even said that I was going to buy her a ring and this stuff, we were always flirting and this kinda stuff. In valentine's day we got in a call and talked a bit, that call made me realize that it won't work because here, pandemic is still pretty bad, school isn't back yet and I didn't want something serious now, not just that, but the call also seemed just a "friend call" it bothered me a bit, even after H said that she had liked it. I said that I didn't think it would work and other stuff to her two days after valentine's, she said that it was fine, but I see she isn't appearing in the group anymore neither is as energetic as she was, it seems that she is again the same shy girl who doesn't talk to nobody, not the girl that used to talk in our private group all the time. After all that i flirted with some other girls (in the same group) but nothing serious.

So, AITB?