Don't Ever Underestimate Yourself

Good morning people....
Today I had 2 subject to be examed. First one isa Interpreting. In this subject I'm sure I can get an A score. I passed it well. But on the other subject (writing) I felt like my world down: (. Actually it's simple exam ever. We just answer what the lecture questioning. Well, I felt nervous when my name is called. I come in the room and suddenly my leacture asked me what score do you want in this subject. And I answer it as true without think it before, I said B+. I wondered it's a joke. Then, he gave me B+ with a laugh. I'm surprise,shock, regret, dissapointed, mad with my self. Honestly I deserve to get A score cause I always present in every meeting, I done my assignments, I posted some unique and interest things. My lecture then asked me "why did you think you deserve get B+?  I want to give you A, but you want B+ ".. I'm shock and answer, "Seriously?I thought it's like a joke, Sir.  I want to get A too." Then he answer, "Sorry, you said like that so I give you what do you want". Out of blue tears are falling from my ayes. I really don't mean like that. So guys, I had learned One thing in my life today. "DON'T EVER UNDERESTIMATE MYSELF". My lecture was sorry  because he want me to learn to be more appreciate myself. Then, I realize that I'm precious. I'm God's original work of art. So don't let onyone tell me that I less then wonderful, even myself. Seriously, I hate to be like that. And I hope whoever who read my post today will avoid to underestimate your own self. I really regret with what I'd done today. This is change my mood. I only want to cry: ( everyday.