How to repare this ?

Hello !
Well, I have a small problem : we texts each others for one month and because we were in exam we don't see each other (I really like him and I think him too for like 3 years) and when we see each other because I really don't know what to do and because I know that if I stare at him, it will be obvious that I liked him, I sort of ignored him...and at a moment I was searching someone in the crowd and I was upset because the person wasn't here.
But then I cross his stare and he was just like staring at me like smiling but a very intimate smile, like and because I was upset I don't have the time to react and I just stare at him like '-' and I just..go away...
After that I was reunited with my friend and him with his (this day we actually know if we pass or not) and then he go with my friends (we were like 7) and let his friends "alone" and my best friend push me to look at him so it was pretty obvious that I don't want to see him, then he looks very...sad, so much that he just go home without saying anything, no goodbye to his friends...
The day after, we were celebrating our results during a party, he should be there and I was ready to confess my feelings to him but he wasn't and there was his brother always like looking at me or being on his phone..
The day after the party I text him and ask why he wasn't there because I really want to see him he just answer that he have a terrible hangover from yesterday ( and he was very cold, not like before ), obviously it wasn't true because there was no party that day I just say something basic after and no answer again

That far I though there was nothing to answer, but I just realize that he's probably upset because I ignored him when we see each other..
The problem is that one month ago I just send him a text just saying hi in order to ask him out for confess my feelings or just date whatever the mood, he doesn't answer because he went to holidays in a country for like one month in which it's very difficult to have grid, so I don't know if he had my text and don't want to answer or if he doesn't have it.. in both cases I don't know if I should re-send a text in few days or not...

Please give me your opinion about his reaction and did I should re send him a text ? Because I don't want to harass him..
I know it's very confused because the story is actually very confusing and english isn't my native language

Oh Lawd...why ignore him when you see him face to face? And how old are you? I'm sorry this just sounds very child-like behaviour...