Nothing makes sense.. Please Help ?

I'm at uni doing my web based and business management but I don't know why it feels like I can't speak, read, or write and nothing makes sense to me but I'm just doing ignments I don't know how and I'm still ping them, I wasn't the cleverest and neither still am but I got lot of help from my lecturers at College and now at Uni I somehow manage to complete all my ignment and never struggle and I don't read books or anything but still complete the ignment. I just ask my friends for help whenever I am stuck and when I can't do anything, and I also think I can't speak very good English because I migrated to England when I was 10 now I am 20, and I don't know where I am going with my life. I just want to kill myself.