Well there this boy ive had a crush for 4 months now. He knows i like him cause my friend told him. Even since we had eye contact in class alot and he worries about me when im sad . Ive never really talk to him. What does this mean?

That probably means that he is interested in you. If you don't really talk then it's pretty much a definite sign that he's into you. I mean, if he has talked to you before then you shouldn't jump to conclusion since you guys know each other. But since that's not the case, then that does mean that he's trying to find some sort of excuse to talk to you.

Plus you say that he's worried about you. That's a pretty good sign! Guys usually don't worry about other people unless they a) like/care about that person (as a friend, family, or otherwise), b) want that person to like them back (usually as otherwise rather than friend or family), c) are severely sympathetic to others, or d) feel like they can gain something from you by being nice to you. As you can see, the odds are in your favor. A and B points that he likes you and C points that he is a really nice guy. D is unlikely but it can happen so it's good to be aware of that.

So that's what I get from your description. I don't really see anything else. I hope this helps.