This was during the fight with Haku, the first time Sasuke's Sharingan showed up in season 1. As you can see, his right eye has two black dots and the left has one.
Kakashi's eye has three dots and this was during a battle with Zabuza, the same season a few episodes earlier before Sasuke's Sharingan showed up when fighting with Haku.
What are the dots inside the eyes when someone uses Sharingan?