You have to say to yourself: I believe that I can beat them all.
You see,belief is a wondrous thing.It can propel you where you only dream to be.
And levis2 ,there are many smart people out there,smarter than you and me.But the funny thing is not all become great mathematicians.Some don't even dare to dream like you do.You have to learn to love yourself unconditionally.Don't say: i'll love myself when i become a great mathematician. Love yourself even if you don't.
One thing that you need to learn is how to vent your feelings.Basically,you have to do something else besides math,something that you like (sport,music,art).This way even if you get stressed about math,you can always let go of that frustration with sport,or whatever, and then go back and solve that math problem.I've also read somewhere that iq grows with years.So don't worry about that.
i believe in you.