I would first send myself the secret code I developed for myself back in high school in case something like that happened/I was about to do something life/world changing, and would send a message to myself with the code. If I remembered where it came from, I had nothing to worry about. The fact that I wouldn't remember where this was from would get me interested.
I'd include in the message something horrifying like "SLENDERMAN"
And after younger me stopped screaming and realized time travel was involved...
"Dude, seriously, it's not a cruel act. That girl totally digs you." Is what I'd say.
"But she's in a lower grade than me!" Is probably what younger me would say. I was 16, she was 15.
"Not my problem anymore. I'm 20, she's 19. Trust me on this one, she's the most beautiful and intelligent girl you'll EVER MEET man! I'm not even kidding, every girl we've dated after this in this ass-backwards state have been mind-numblingly stupid sheeple!"
And then absolutely nothing would be resolved because I was a socially retarded little twat.