is this what a first love is?

Normally i don’t go on here for anything other than exam help but i know there’s a relationships section… this post might be a bit long but i just want to let this out.
i have a really good friend.. in some ways he’s my best friend.. to be honest i dont know how to define it.
I met him a bit more than a year ago and we spoke a couple of times when we met but nothing crazy. The months after we met he would message me every so often and just make conversation and slowly we spoke more and more often. I didnt catch feelings for him immediately.. at first i just appreciated him as a friend but the more we spoke the more i started to realised that i dont want to lose contact with him.
Talking to him felt like such a breath of fresh air. Whilst i have a lot of friends and always have had a lot of friends, i’ve always felt like i lacked connection to them - like there was some kind of barrier between me and them where i couldnt 100% be myself but when i talk to him thats not there. We could talk for hours about nothing in particular and it would feel so comfortable. I could tell him about everything i’m interested in without fear of being judged and it was just so easy. When i did realise how much it would upset me if we lost contact i started to realise that i began to develop some kind of feelings. I didn’t say anything for a while but when i did i was rejected but from that day we became closer than ever and we started speaking every single day. I still feel the same way and i want to just tell him how much i appreciate him and how he brightens my day and how i dont want to lose him but i have terrible social anxiety and i dont want to ruin what we have as friends. All i’m really wondering is if this strong feeling is what you’d call a first love. To be honest i always felt like love was such a strong word but i don’t even know what to call my feelings or how to even make sense of them.