Goodbye Dr.Tan, Hello Maths

I am a student who is afraid of maths, a lot. Especially when it comes to calculus. It is called "advanced maths"! How can I manage to understand! But I also hate history, so it's very hard for me to choose a major...
As we all know, on Fridays, we will not attend English classes, wo will go to study calculus or C programming or something else. At first, we attended lectures related to personal hygiene, some serious diseases and doing exercise properly held by Dr.Tan, a lecturor that can make us laugh and laugh, I think if there something wrong with myself, I will absolutely long for a doctor like him. What I couldn't figure out is the reason why there were students sleeping during HIS lecture! How come this happened? Maybe they had had poor sleeping quality, I think. But sunny days finally passed. We must say farewell to Dr.Tan, because we are supposed to attend lectures about maths and C programming, which is my nightmare and dread. It finally came to me last Friday. To my astonishment, we didn't learn some difficult stuff. The lecturor of C programming had prepared a lecture about elements of a PC to kindle our interest to his class, and the maths teacher wasn't as prim as I had thought. To be brief, personally, I had a charming Friday, but maybe as time goes by, I will feel awful sooner or later...But...whatever, let's wait and see.