First teaching practice, Technical english

Hi mates, today I had my practice with technical english. I created my lesson plan which was about possessive adjectives and pronouns. I realized that all of them were girls like the last semeter. I didn't know anything about the group, so I felt a little nervous because I always feel nervous the first day of teaching because I don't know how students are going to react. First, I introduced my self and got a little familiar with them. Then, I asked them about the topic they were studying. Some of them were absent minded because they had no idea what to say. Since it is technical english I, I think it is very hard for them because they are from another major.
As a warm up activity, I brought a bag in which I asked them to place some personal objects, everybody collaborated by putting something inside the bag, and at the end, one by one picked up one object and I asked her, "whose pencil is that?" and they had to tell me, "this pencil is hers". I think it was a nice practice since they were going to use almost the same structure, but different noun. Then, I made an oral activity and I asked them to make groups of three. I wrote an example of the activitiy on the board and told them to follow the example. I called the three persons from the group and I said the first girl a sentence like this. I get a cellphone; the student had to tell that sentence to her classmate, and her classmates had to say, "This is my cellphone"and the other student had to say, "this cellphone is mine". If they all said the sentence correctly got a point as a group.  I think they liked the activity, but it was a little confusion , but I noticed they were trying their best to say it correctly. They seemed intersted in the activity. After, that I wrote it on the board and asked them to do the same in a written form. When they finished, I told them to repeat all the answers , that was fun because some of them said something different, but I let them know the correct sentence. Later, I wrote  a dialogue which they had to filled up the blanks with some words according to some prounouns and other words. They worked on that, but some of them seemed to have problems even with very basic things, that they were supposed to know already. I made them repeat the dialogue twice and asked if there were questions. Then, I continued with an oral activity which I think it was not appropriate because I think it was too difficult for some of them because there were only 3 girls answering what I was requiring. Well, this was all what I can say about my experience in my first day at technical english I.