My first class with the intermediate I (=

As any first time  knowing a group in the first class, I started a little bit nervous but as soon as the students arrived into the class  I was feeling better because I remember that those were the same students with  I was with the last semester in my practice.
I started my class by letting the students know about the purpose of the class and by telling them what I was expecting to achieve in that hour.
I love the way the students were trying to particpate in the class and also what comfortable they made me feel during the time that I was there.
I started my class reviewing about the topic that I was assigned; I got some problems to get information about the the topic which was Rejoinders because the lesson plan was not ready so I had to look for the material. I prepared for my class like around 4 activities which were nice.
After I got the feedback, I realized that I was not that prepare as I am supposed to be because the warm up activity was just a review of the topic and it was not really funny so I saw the students a little  bit sad, tired or bored. The teacher told me that I should always prepare a game for the first moment of the class because the students need to relax before starting the class. It perfectly knew about the importance of a warm up activity in every class but I got confused because the last time the same teacher told me that I should not be just playing in the class, and that the warm up activity should be completely depending on the topic to be teach.
I felt sad after knowing that because the last time I was teaching with him I played too much and today the class was not really dynamic jajajajjaja .... )= Too bad for me
I know that the next class can be better, I am really expecting to finally have a lesson plan for the level and have the information on what I have to teach in advance because it is really hard to prepare classes when you dont have the material........