I feel bad..i might have hurt his feelings without knowing at the time..now he not talking 2 me?

This guy(Trey) and i are attracted to each other. I have to wait until after summer school to even go out with him because i'm so busy. When we see each other at school its great..but last time on the way to say hi to him a guy (Chris)came up and said hi and i started to talk to him. After that i sort of walked away and went to do my own thing because i got nervous to go up to Trey especially because now he was talking to one of his guy friends.(I get shy when i have to go up to a guy who is with someone else..) i walked away to hope for another opportunity to say hi. But he left early and ignored me. A friend told me i looked like i was flirting with Chris but i truly didn't think i was.Now trey won't call and text and stuff. What do i do without actually bringing it up..about him ignoring me?