Crying is useless

Everything went wrong lately. I have tried my best to face whatever obstacles that are blocking my way to success but my hard work doesn't seem to pay off.I have somehow given up on trying and tired of working hard everyday but gaining nothing. I am not happy even though when I get high marks for my other classes because I have strong feeling that I am going to fail my c++ course. I feel like I have spent most of time on this course and yet I just couldn't do well. Is it true that I can only do things that I am good at?Does it mean that I could never succeed no matter how hard I have tried?I know that crying is useless but even if I did something useful,it still won't work.I went to TA office hours,lab hours,making appointment with my TA,sending email to my TA......Is there anything else that I can try?I really hate myself crying and having to admit that I am not smart enough to be computer science major.In the past few years,I had been holding back my tears and I only cried alone under the moonlight but now I just can't stay strong anymore.I have lost my balance of life.I hope people who love me are by my sides when I need them most but nobody is there.I have put too much burdens on my shoulders and yet I know that I can't really let them go.I don't want to see my puffy eyes when I stand in front of the mirror again and yet crying is my only way.Sorry for making you all listen to me crying on the phone.I promised that I won't do that again.