Am I in love?

I(23m) think i’m in love for the first time ever with this girl(21f) There’s this girl… and every time I think about her I smile, when she texts me back I smile, when she shows any type of attention or affection towards me I smile, and I can’t help it. I’ve never been in love and I don’t think I know what love is or what it feels like but this one had me questioning whether I am in love. We had a past and we used to talk everyday despite being long distance, and she was really the only girl that I could ever keep a conversation with that actually cared, she’s always cared about my absence, my words, my thoughts, and my what I do in my life and that kinda really makes me happy. We’ve been kinda talking to each other on and off and were basically in a relationship for a few months before I broke it off, but the thing is, I only broke it off because i’ve never had my feelings and emotions left in the hands of anyone but myself. I really feel like she stole my heart tbh. I was in a one year relationship after her and I realized that I would constantly compare my current situation with what me and my past shared along with this girl who I cant get off my mind. I just recently broke up with my now considered ex and since then I’ve just been thinking about this girl that used to understand me so well and would bring so much peace and joy into my life. Not even just that, her beauty to me is so indistinguishable from anyone else i’ve ever known and I really can’t help but to ask and wonder, am I in love? Is that what love feels like? Should I pursue?

Tldr I think i’m in love with a girl from my past