Thinking positively is really very important in the journey of A/L science stream. In the path of A/L there is always ups and downs. 

Since we are humans, sometimes our mind utters..

"I couldn’t study well. I'm not going to make it out in A/L’s.
I'm going to give up….. Bla bla bla".

In this case I'm also not an exception. I had the same feelings sometimes.