Today, I had classes from the third period to the fourth period. Both were English classes; the third period was a presentation, and the fourth period was a test. My test results were okay. After school, I have to go to the hospital. When I get home, I’ll work on the presentation for the fourth period tomorrow.

You explained your day really clearly! I’d just change a couple of phrases to make them sound more natural: “Today, I had English classes during the third and fourth periods. I gave a presentation during the third period and had a test during the fourth.” Also, “my presentation for tomorrow’s fourth-period class” sounds a little more natural 😊