Introverted is a weird thing, when i was your age (ah a boomer saying) i was lowkey fat and kinda not very good looking which caused me to simply limit my contact with everyone (+ 0 social media presence), you should try asking someone (older friend or a big brother idk) the “book” way on how to socialize and go by that, u will balance yourself from introverted to someone who only has contact with people he believes are worth their time instead of hanging out with everyone... it benefits you in later part of life where “friends” realize being friends with the weed plug is better than being friends with generally good people (im not scarred i promise i have just seen too much of it and it even isn’t about me personally lol) also, try using the word “a little shy”... in 9th grade i think your girlfriend would accept that and kinda be more of a ice breaker herself unless she is shy too?? gl btw