It is not good to be feeling like this.  I am a mom, and a person who has spent a lifetime feeling like I am not quite good enough.  I have recently found it that a lot of what I was feeling was linked to depression and I didn't even know it.  I am not saying that is what is going on with you, but it never hurts to talk with your doctor - in my case, if I had known about it in my teens, things would have been MUCH better.  Grades aren't everything.  You need to talk to a parent, teacher or another adult that you feel you can trust and talk about what is going on.  My brother is an extremely bright person - as in he was professionally tested and had a crazy high IQ.  He went through school with a nice solid C average.  He bummed around in waiter and retail jobs for a long time before figuring out what he wanted to do and how to go and get it.  He is just starting a job that he is actually liking that provides on the job training - he is 32.  There is a lot of pressure for you to walk out of high school know what you want to do, what schooling you want to do etc. etc.  The only thing you need to worry about is knowing if you did the best job YOU can do.  Don't compare yourself to others - every one has strengths and weaknesses, it doesn't mean anything.  If you know that when you got those grades you had done the best you could do then don't worry about.  If you know that you could have done better, than do it.  You need to be able to live you life according to your own measure - not other people's.  You are young, you have a long time to figure out where you want to go in this world.  Take your own path, know what you want.  You will be much happier than if you are trying to make other people happy.  Please don't do anything permanent.  I hated being 13, but it truly does get better.  There are people all around that can help you through this.  Go and find them.  Don't give up.