Giving Up Something That I Want To Improve

[ROOKIE OF THE YEAR]

Today, I get went to my first class of Muay Thai training. I've been dreaming of boosting my confidence, self-esteem, and mental thoughts through martial art trainng. I chose muay thai because I found it very interesting, which it is. But the problem is that I just learn that learning these kind of things including self-defense was not cruise at all.
I lacked a lot of stamina, and worse of all, my sensei make me kick a kicking punchbag for 2 sets. He guarantee me that it won't not break my feet. But I feel pain, I never thought the sandbag is that hard. I was scared to because I had to do 10 reps a set each leg as hard as i can.
After class, I feel very exchausted, and I have to do this again on monday.
I've been wanted to learn some martial class for confidence for a very long time. But I realize I am even more worry more than before.
According to the instruction, it will guarantee to make me a better person. But now i am afraid.
I really really really don't want to give up my goal of muay thai. But my fear and pain is telling me to give it up. But if I do, I am just have stick with being a insecure ***** and get pick-on at school again.
Can anyone give me some pointers on not giving up pain and exhaustion? My muay thai class mate said this is a fun class, but what fun is pain? How can I pass this kicking the sandbag without cheating, which my sensei knew today?
I really don't want to give up, my I afraid, it's like dont have any choice but give up.

 

[ROOKIE OF THE YEAR]

My sensei said I pain is all in my mind. He said my thought is the reason why I feel this pain from kicking on the sandbag, just dont think about it. But how can I not feel pain. I was so close from crying.

 

[King of You]

dont be such a gotdamn whiny *****. muay thai is one of the most viscious professional fighting styles there is. what did you think it was gonna be? cake and ice cream? You want something easy try joining the ages 10-13 karate class at the local strip mall.

 

[Reiki]

If your looking to be a professional, you will have to do it, if you just want to learn self-defence and gain a bit of confidence, try looking more towards krav maga or systema styles, but it really all comes down to your trainer, some trainers know how to adapt muay thai to self-defence.